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Cancer patients experience weight loss for a variety of reasons, commencing with the tumor’s metabolism (Warburg effect) and proceeding via cachexia to loss of appetite. In pancreatic cancer, several other factors are involved, including a loss of appetite with a particular aversion to meat and the incapacity of the pancreatic gland to function normally when a tumor is present in the pancreatic head. Pancreatic exocrine insufficiency is characterized by a deficiency of the enzymes secreted from the pancreas due to the obstructive tumor, resulting in maldigestion. This, in turn, contributes to malnutrition, specifically a lack of fat-soluble vitamins, antioxidants, and other micronutrients. Patients with pancreatic cancer and pancreatic exocrine insufficiency have, overall, an extremely poor prognosis with regard to surgical outcome and overall survival. Therefore, it is crucial to be aware of the mechanisms involved in the disease, to be able to diagnose pancreatic exocrine insufficiency early on, and to treat malnutrition appropriately, for example, with pancreatic enzymes.

OBJECTIVE Curing type 1 diabetes by transplanting pancreatic islets into the liver is associated with poor long-term outcome and graft failure at least partly due to inadequate graft revascularization. The aim of the current study was to evaluate striated muscle as a potential angiogenic site for islet transplantation. RESEARCH DESIGN AND METHODS The current study presents a new experimental model that is found to be applicable to clinical islet transplantation. Islets were implanted into striated muscle and intraislet vascular density and blood flow were visualized with intravital and confocal microscopy in mice and by magnetic resonance imaging in three autotransplanted pancreatectomized patients. Mice were rendered neutropenic by repeated injections of Gr-1 antibody, and diabetes was induced by alloxan treatment. RESULTS Contrary to liver-engrafted islets, islets transplanted to mouse muscle were revascularized with vessel densities and blood flow entirely comparable with those of islets within intact pancreas. Initiation of islet revascularization at the muscular site was dependent on neutrophils, and the function of islets transplanted to muscle was proven by curing diabetic mice. The experimental data were confirmed in autotransplanted patients where higher plasma volumes were measured in islets engrafted in forearm muscle compared with adjacent muscle tissue through high-resolution magnetic resonance imaging. CONCLUSIONS This study presents a novel paradigm in islet transplantation whereby recruited neutrophils are crucial for the functionally restored intraislet blood perfusion following transplantation to striated muscle under experimental and clinical situations.

The association between chronic pancreatitis (CP) and primary sclerosing cholangitis (PSC) has been reported previously. The aims of the present study were to evaluate the presence of early pancreatic abnormalities and duct changes, using MRCP/MRI in PSC and to evaluate possible risk factors for these changes and their clinical importance.One hundred and three patients with PSC were identified among all MRI liver/pancreas referrals in 2001-2005. MRCP was used to grade pancreatic duct changes in three groups: grade 0 (normal), grade 1 (mild) and grade 2 (severe). For detection of early MRI signs of CP, the pancreas-spleen signal intensity ratio (SIR), the arterial and early venous phase ratio (A/PV ratio) and the age-related size of the pancreas were evaluated.Pancreatic duct changes were found in 24% of the PSC patients. The pancreatic duct changes were associated with extrahepatic biliary involvement and long duration of PSC but not associated with pancreas-spleen SIR, A/PV ratio, pancreas size, previous post-ERCP or acute pancreatitis. Severe pancreatic duct changes were significantly associated to abdominal pain. Clinically significant CP was seen in one PSC patient (1%).Pancreatic duct changes are associated with extrahepatic bile duct strictures and not with the early MRI signs of CP. Therefore, pancreatic duct changes seem to be part of the spectrum of PSC and should not be defined as CP. Pancreatic duct changes are of limited clinical importance but may contribute to abdominal pain in PSC.

Objective: To evaluate whether upregulation of liver and muscle uncoupling protein 2 (UCP-2) is an acute phenomenon in obstructive jaundice and associated with secondary metabolic effects. Methods: Male Sprague-Dawley rats were divided into four groups bile duct ligated (BDL) and sham-operated pair-fed (PF), ad libitum fed (AL), and controls BDL. PF. and AL rats were further divided into subgroups according to the interval postoperatively when they were reanesthetized and sampled for tissue and blood 2, 4, and 8 d, respectively Bilirubin, liver enzymes. glucose, free fatty acids, and insulin in blood plasma were analyzed Liver and muscle tissue were sampled for UCP-2 and adenosine triphosphate analysis. Results: The BDL rats showed an increase of the liver UCP-2 expression compared with PF and AL rats (P < 0 05) 4 d postoperatively. Liver adenosine triphosphate in BDL rats showed a decrease compared with sham-operated controls at all intervals < 0 05) Plasma glucose concentration in BDL rats was decreased compared with the other groups. Free fatty acids showed an initial increase 2 d postoperatively compared with sham-operated controls and PF and AL rats (P < 0 05) at the corresponding time point Conclusion: Obstructive jaundice is associated with an early upregulation of liver UCP-2. reduced liver adenosine triphosphate content, and decreased plasma glucose concentration, supporting the hypothesis that obstructive Jaundice results in impaired energy homeostasis in the liver. which might cause decreased glucose output and hypoglycemia as a consequence (C) 2010 Elsevier Inc. All flats reserved (Less)

A 7-year-old girl with severe hereditary pancreatitis underwent total pancreatectomy. A total of 160,000 islet equivalents (6400 islet/kg) were transplanted to the brachioradialis muscle of the right forearm. Her plasma C-peptide level was undetectable after pancreatectomy but increased to 1.37 ng/mL after 17 days; at this time point, her insulin requirement was 0.75 units of insulin/kg/day. At 5- and 27-months, her hemoglobin A1c (HbA1c) and insulin requirements were 4.5 and 5.3% and 0.3 and 0.18 units/kg/day, respectively. Basal and stimulated C-peptide levels were 0.67 +/- 0.07 and 3.36 +/- 1.37 ng/mL, respectively. Stimulated insulin levels were 30% higher in the islet-bearing arm compared to the contralateral arm after glucagon stimulation. After surgery and islet transplantation, the quality of life improved dramatically and she gained 8 kg of weight. In summary, a normal HbA1c, a low insulin requirement and the absence of recurrent hypoglycemia and the gradient of insulin between the arms indicate that the intramuscularly transplanted islets contribute to a long-term clinically significant metabolic control.

Intratumoral hypoxia and paracrine insulin stimulate the expression of hypoxia inducible factor-1alpha (HIF-1alpha) in pancreatic cancer cells. In the present studies, we investigated whether insulin-induced HIF-1alpha expression is a prerequisite for insulin to induce other trophic effects in MiaPaCa2 human pancreatic cancer cells and whether inhibition of HIF-1alpha expression would decrease tumor glycolysis and improve host energy homeostasis. We found that hypoxia was a prerequisite for induction of HIF-1alpha mRNA expression by insulin in MiaPaCa2 cells. Under hypoxic conditions, insulin stimulated glycolysis, cell proliferation, and the secretion of vascular endothelial growth factor in regular MiaPaCa2 cells but not in a MiaPaCa2 variant (si-MiaPaCa2) that expressed specific short interfering RNA for HIF-1alpha and therefore lacked HIF-1alpha protein. This suggests that HIF-1alpha expression is required for insulin to induce other trophic effects. When si-MiaPaCa2 cells were transplanted into the pancreas of athymic mice, they were less tumorigenic and expressed less hexokinase than regular MiaPaCa2 cells. Body weight gain was attenuated in mice hosting tumors composed of regular MiaPaCa2 but not si-MiaPaCa2 cells. These results suggest that an interaction between insulin and HIF-1alpha helps sustain pancreatic cancer cells and disturbs host energy homeostasis.

This experiment investigated the influence of age on prefrontal acetylcholine (ACh) release and Fos response in the hypothalamic paraventricular nucleus and the nucleus tractus solitarius (NTS) of rats following isoflurane anesthesia. It is known that isoflurane decreases acetylcholine release in most brain regions. In the present study, we found that the level of prefrontal acetylcholine was significantly lower in 28-month-old rats (14% of baseline) than in 3-month-old rats (38% of baseline) during 2 h of isoflurane anesthesia (P < 0.05). The old rat group showed significantly greater Fos induction in the paraventricular nucleus compared to the young adult rat group (P < 0.05), indicating that the old rats were subjected to stress. No difference in Fos response was noted in the nucleus tractus solitarius. The old rats displayed a significant increase in feeding behavior during the 3-h recovery period (P < 0.05), but there was no difference in overall acetylcholine levels. Taken together, these findings suggest that isoflurane anesthesia influences old rats more profoundly than young adult rats with regard to reductions in acetylcholine release and stress responses. This may have implications for understanding the development of postoperative delirium in aged patients.

Amylin is postulated to act as a hormonal signal from the pancreas to the brain to inhibit food intake and regulate energy reserves. Amylin potently reduces food intake, body weight, and adiposity when administered systemically or into the brain. Whether selective blockade of endogenous amylin action increases food intake and adiposity remains to be clearly established. In the present study, the amylin receptor antagonist acetyl-[Asn30, Tyr32] sCT-( 8 – 32 ) (AC187) was used to assess whether action of endogenous amylin is essential for normal satiation to occur. Non-food-deprived rats received a 3- to 4-h intravenous infusion of AC187 (60–2,000 pmol·kg−1·min−1), either alone or coadministered with a 3-h intravenous infusion of amylin (2.5 or 5 pmol·kg−1·min−1) or a 2-h intragastric infusion of an elemental liquid diet (4 kcal/h). Infusions began just before dark onset. Food intake and meal patterns during the first 4 h of the dark period were determined from continuous computer recordings of changes in food bowl weight. Amylin inhibited food intake by ∼50%, and AC187 attenuated this response by ∼50%. AC187 dose-dependently stimulated food intake (maximal increases from 76 to 171%), whether administered alone or with an intragastric infusion of liquid diet. Amylin reduced mean meal size and meal frequency, AC187 attenuated these responses, and AC187 administration alone increased mean meal size and meal frequency. These results support the hypothesis that endogenous amylin plays an essential role in reducing meal size and increasing the postmeal interval of satiety.

Obesity is associated with increased severity in patients with acute pancreatitis (AP). The underlying mechanisms are unknown. Genetically obese rats exhibit decreased survival rate in experimental AP, but the clinical relevance of this model of obesity may be questioned. It is proposed that development of organ failure in AP occurs in two stages: initial priming of leucocytes followed by a second inflammatory attack. The aim was to evaluate the impact of diet-induced obesity on outcome in a 'two-hit' model of AP.Lipopolysaccharide (LPS) was injected i.p. 3 h after retrograde bile duct infusion of sodium taurocholate in rats. Three experiments were done: 1) an LPS dose-response experiment, 2) chronic high-fat feeding (HF) for 16 weeks, and 3) acute HF for 10 days. Control rats received normal chow. Obesity, morphology and survival rate were assessed.LPS dose-dependently decreased survival rate and increased morphological severity. HF increased weight, intra-abdominal and liver fat. Only acute HF induced hyperlipidaemia. In AP, acute obese rats exhibited less pancreatic inflammation, but total histological severity between groups was not different. In the chronic experiment only obese animals succumbed before 24 h of pancreatitis, but 72-h survival rate was not statistically different in either high-fat experiment.An addition of LPS to AP decreases survival rate and intensifies the peri-pancreatic processes. Despite significant obesity, neither hyperlipidaemia nor increased intra-abdominal or hepatic fat influenced local pancreatic injury or survival negatively. The amount of fat per se seems not to be responsible for the deleterious influence of obesity on acute pancreatitis.

OBJECTIVE: Hyperglycaemia associated with insulin resistance is common after trauma and surgical procedures. Both reduced insulin sensitivity and altered insulin secretion may contribute to the impaired glucose homeostasis. We have demonstrated that skeletal muscle insulin resistance is present 2 h after small intestinal resection in rats. In this study, the aim was to investigate insulin secretion in the same experimental model. DESIGN: Small intestinal resection (5 cm) was performed in adult rats. The control animals underwent anaesthesia only. METHODS: The intravenous glucose tolerance test (IVGTT), the hyperglycaemic clamp and in vitro studies in isolated pancreatic islets were performed after surgery. Concentrations of blood glucose, plasma insulin, corticosterone and interleukin-6 (IL-6) were determined 0-5 h postoperatively. RESULTS: The insulin response in the IVGTT was attenuated 2 h (P

Metabolic stress after surgery is associated with peripheral insulin resistance. Recent studies have suggested that preoperative glucose can ameliorate postoperative decreases in insulin-stimulated glucose disposal. In the present experiments, we used a bowel-resection model of surgical trauma to test the hypothesis that elevations of serum insulin induced by preoperative oral glucose or ad libitum feeding affects postoperative insulin-stimulated glucose uptake in skeletal muscle. Insulin-stimulated glucose transport was measured in vitro in soleus muscles after surgical trauma in fasted rats given oral glucose or water before surgery. Insulin-stimulated glucose transport was also assessed in vitro in fasted or fed traumatized rats and non-traumatized control animals. In addition, stress hormones (glucagon, corticosterone, and adrenaline) were measured before and after surgical trauma in fasted rats and rats fed ad libitum. In vitro skeletal-muscle insulin sensitivity and responsiveness were reduced postoperatively in fasted animals that received oral glucose loads before bowel resections and in rats fed ad libitum or fasted before surgery versus non-traumatized rats (all P < 0.05). Stress-hormone concentrations after trauma did not differ between fed and fasted animals. In the current study, insulin sensitivity and responsiveness were reduced in isolated skeletal muscles after bowel resection, but neither preoperative glucose supplementation nor free intake of mixed nutrients ameliorated the development of postoperative insulin resistance.

Islet amyloid polypeptide (IAPP or amylin) potently reduces food intake in rats at or near physiological concentrations. Although the mechanisms of action of IAPP are not understood, the brain is a suggested site. Changes in hypothalamic and striatal neurotransmission have been reported following acute systemic administration of a pharmacological concentration of IAPP. In the current study, we evaluated the effects of chronic administration of low doses of IAPP on satiety-related neurotransmitters and neuropeptides in the hypothalamus, hippocampus, striatum, left cortex, and right cortex of the rat. Doses of 0, 5 and 25 pmol IAPP/kg-min were administered subcutaneously for 2 or 5 days. Food intake was reduced by 27 and 44% (both P0.001) for the 5 and 25 pmol/kg-min groups, respectively, in the 2-day experiment and was decreased by 14% (P0.01) and 24% (P0.001), respectively, in the 5-day experiment. Body weight was significantly decreased in a dose-dependent fashion. In the 2-day experiment, norepinephrine increased in the hypothalamus in the 5 pmol IAPP/kg-min group, and neurotensin increased in the hippocampus in the 25 pmol/kg-min rats (both P0.05). In the 5-day, 5 pmol/kg-min rats, 5-hydroxyindoleacetic acid (5-HIAA) increased in the hypothalmus and cholecystokinin (CCK) increased in the striatum (both P0.05). In the 5-day, 25 pmol/kg-min group, neuropeptide Y (NPY) increased in the hypothalamus (P0.01) and CCK increased in the hypothalmus and striatum (both P0.05). The present study confirms that IAPP is a potent anorectic peptide at low doses and suggests that IAPP not only affects classical neurotransmitters in the brain but also alters concentrations of neuropeptides known to be involved in food intake.

Introduction: Enteral feeding has been reported to increase intestinal mucosa proliferation after resection. Dietary components influence the intestinal adaptive response. The purpose of this study was to evaluate the effect of ornithine- (OKG) or arginine-ketoglutarate (AKG) bolus supplementation on intestinal postresectional adaptation in the rat. Methods: Male Wistar rats underwent 65% small-bowel resection and received either OKG 3 g/kg/day, isonitrogenous AKG or saline by gavage once daily. The animals had free access to rat chow. Sampling was done 10 days after resection. Fed animals without surgery or specific treatment served as controls. Results: Mucosal wet weight, DNA, RNA, protein content and sucrose activity of the mucosa, as well as villus height were significantly increased in all resected animals compared to controls. No significant differences in body weight or intestinal adaptation could be found between the three dietary groups. Conclusion: Postoperative enteral bolus feeding supplemented with OKG or AKG did not significantly enhance the adaptation of the remnant small bowel 10 days after massive intestinal resection when rats had free access to rat chow. © 2000 Elsevier Science Inc.

Glutamine is the principal energy source for enterocytes, but it is not known whether parenteral or enteral supplementation is most ben- eficial to gut integrity. The aim of this study was to evaluate the effects of glutamine in uni- or bidirectional supply on the viability of intestinal mucosa of starved rats during incu- bation in Ussing chambers. Seg- ments of jejunum from rats starved for 48 h were randomly mounted in Ussing chambers with three nutrient solutions: Krebs buffer without glu- tamine; 6 mM glutamine added to the mucosal side; 6 mM glutamine added to the mucosal side and 0.6 mM glutamine to the serosal side. ATP content of the mucosa, electrophysiology, and 51 Cr-ethyl- enediaminetetraacetate (EDTA) per- meability were studied during 180 min of incubation. The addition of glutamine to both sides of the stripped mucosa improved ATP lev- els compared to the Krebs solution (P

Pancreatic carcinoma is characterized by poor prognosis and lack of response to conventional therapy for reasons that are not clear. Because of the structural relationship between the exocrine and endocrine pancreas and high concentrations of islet hormones bathing pancreatic tissue, we hypothesized that pancreatic cancer cell proliferation and glucose utilization are regulated by pancreatic islet hormones, particularly insulin. Based on this, the effect of islet hormones on pancreatic cancer cells in vitro was investigated. Five pancreatic cancer cell lines, CD11, CD18, HPAF, PANC-1, and MiaPaCa2 were used to investigate the effect of islet hormones on cell proliferation, glucose utilization, and GLUT-1 expression. Insulin, but not somatostatin and glucagon, induced pancreatic cancer cell growth in a concentration- and time-dependent manner. At concentrations within the range of those in the intrapancreatic vasculature, insulin (10(-10)-10(-8) mol/L) markedly increased [3H]-thymidine incorporation. Insulin significantly enhanced glucose utilization of pancreatic cancer cells before it enhanced cell proliferation. The MAPK kinase inhibitor PD 098059 abolished insulin-stimulated DNA synthesis and partially reduced insulin-stimulated glucose uptake. In contrast, the PI3 kinase inhibitor wortmannin substantially inhibited insulin-induced glucose uptake and partially blocked thymidine incorporation. Furthermore, after 24-hour treatment with insulin, GLUT-I expression in pancreatic cancer cells was markedly increased, indicating that insulin enhances glucose utilization partly through increasing glucose transport. These findings suggest that insulin stimulates proliferation and glucose utilization in pancreatic cancer cells by two distinct pathways. Insulin augments DNA synthesis mainly by MAP kinase activation and glucose uptake mainly by PI3 kinase activation and enhancement of GLUT-I expression. High intrapancreatic concentrations of insulin are likely to play an important role in stimulating pancreatic cancer growth indirectly by increasing substrate availability as well as by direct action as a trophic factor.

The diabetes that frequently occurs in pancreatic cancer patients is characterized by profound peripheral insulin resistance. The intracellular mechanism of this insulin resistance was investigated in skeletal muscle biopsies from pancreatic cancer patients with or without diabetes and control subjects. Insulin receptor (IR) binding, tyrosine kinase activity, IR messenger RNA (mRNA), IR substrate-1 content, GLUT-4, and GLUT-4 mRNA content were all normal in pancreatic cancer patients. In contrast, multiple defects in glycogen synthesis were found in pancreatic cancer patients, especially in those with diabetes. Glycogen synthase I activity, total activity, and mRNA levels were significantly decreased in pancreatic cancer patients compared with controls. The fractional velocity of glycogen synthase was decreased only in the diabetic pancreatic cancer group. Glycogen phosphorylase a and b activities were increased in diabetic pancreatic cancer patients, but glycogen phosphorylase mRNA levels were not significantly different. The insulin resistance associated with pancreatic cancer is associated with a post-IR defect, which impairs skeletal muscle glycogen synthesis and glycogen storage.

The diabetic state that is seen at a high frequency in association with pancreatic cancer is characterized by elevated plasma levels of several islet hormones and by marked insulin resistance. Both the diabetic state and insulin sensitivity improve after tumor removal by sub-total pancreatectomy. Impaired glucose tolerance has also been found in the hamster pancreatic cancer model, but conflicting data regarding islet function have been reported. In order to further investigate islet function and secretion during early development of pancreatic cancer, we measured the concentrations of insulin, glucagon, somatostatin, and islet amyloid polypeptide (IAPP) in plasma, pancreatic tissue, and secretin-stimulated pancreatic juice at 12 and 27 weeks after the ductal-cell-specific carcinogen, BOP had been used to induce tumors in Syrian golden hamsters. At 12 weeks after BOP, plasma glucagon levels were significantly increased. An exaggerated plasma-glucose response and concomitant hyperinsulinemia were observed at 27 but not 12 weeks after BOP. Plasma IAPP concentrations, but not glucagon or somatostatin, were elevated at 27 weeks. Tissue concentrations of IAPP were substantially reduced in BOP-treated hamsters at 27 weeks. No differences in hormone concentrations were seen in pancreatic juice from the two groups at either of the two time points investigated. The study showed that islet hormone changes accompany the early development of pancreatic tumors in the hamster pancreatic model. The hormone changes and apparent insulin resistance resemble the metabolic changes found in humans with pancreatic cancer.

Islet amyloid polypeptide (IAPP, or amylin) is produced in pancreatic β-cells. The intraislet significance of IAPP is still uncertain. In the present study, paracrine effects of endogenous IAPP and somatostatin were investigated in isolated rat pancreatic islets. The intraislet IAPP activity was inhibited with an IAPP antiserum or a specific antagonist [IAPP-(8—37)]. Somatostatin activity was inhibited by immunoneutralization. Basal insulin and glucagon secretion were not affected by the somatostatin and/or IAPP blockade. Arginine-stimulated insulin and glucagon secretion were dose dependently increased by IAPP antiserum, IAPP-(8—37), and somatostatin antiserum, respectively. Arginine-stimulated somatostatin secretion was dose dependently potentiated by IAPP antiserum. Insulin secretion induced by 16.7 mM glucose was enhanced by IAPP antiserum and IAPP-(8—37), respectively. A combination of somatostatin antiserum with IAPP antiserum or IAPP-(8—37) further enhanced the arginine-stimulated insulin and glucagon secretion compared with effects when the blocking reagents were used individually. These results indicate that endogenously produced IAPP tonally inhibits stimulated insulin, glucagon, and somatostatin secretion. Furthermore, the paracrine effects of IAPP and somatostatin are additive.

The development of front-line endoscopic technology has introduced new opportunities during endoscopic retrograde cholangiopancreatography (ERCP) to single-handedly allow direct inspection of detailed structures of the biliary and even the pancreatic duct. This paper presents a new flexible technology delivered with an outer diameter of 0.9 mm giving an image transmission of 6000 pixels. We report on a case where direct inspection of an alleged duct defect, of potential pathogenetic significance, was considered essential in order to substantiate the subsequent clinical management.

The cytotoxic anti-cancer purine nucleoside analogs 2-chloro-2'-deoxyadenosine (CdA), 9-beta-D-arabinofuranosylguanine (araG), and 2',2'-difluorodeoxyguanosine (dFdG) are phosphorylated by human mitochondrial deoxyguanosine kinase (dGK) in vitro. We overexpressed dGK as a fusion protein to the green fluorescent protein in the human pancreatic cancer cell lines PanC-1 and MIA PaCa-2 to determine the importance of dGK-mediated nucleoside analog phosphorylation. The transfected cells showed mitochondrial fluorescence patterns, and the mitochondrial locations of endogenous and overexpressed dGK were verified by Western blot analysis of cell extracts with polyclonal anti-dGK antibodies. The increase of dGK activity in the overexpressing cells was approximately 4-fold. These cell lines exhibited increased sensitivity to CdA, araG, and dFdG as compared with the untransfected parent cell lines. This is, to our knowledge, the first demonstration of a correlation between the activity of a mitochondrial deoxyribonucleoside kinase and the cytotoxicity of nucleoside analogs. Our data imply that the dGK activity is rate-limiting for the efficacy of nucleoside analogs in the cell lines investigated.

Luminal nutrients and growth factors regulate postresectional intestinal growth. The interplay between glutamine and regulatory gastrointestinal peptides is not known.The effects of intestinal resection on tissue and plasma concentrations of peptides were studied in 60 Sprague-Dawley rats divided into resected, transected, or unoperated groups. Subgroups were fed either a glutamine-free or a glutamine-supplemented diet for 7 days. Epidermal growth factor, transforming growth factor-alpha, insulin-like growth factors (IGF) I and II, peptide YY (PYY), and enteroglucagon were analyzed in intestinal mucosa and in portal plasma by radioimmunoassay.No glutamine-specific effects were seen. The mucosal content of IGF-II (P0.01) and the portal levels of enteroglucagon and PYY (P0.05-0.01) increased after intestinal resection.The increase in PYY and enteroglucagon in portal blood supports a hormonal role in the postresectional adaptation. The increase in IGF II in the ileal mucosa, without changes in plasma, implies autocrine or paracrine growth stimulation at this stage after resection.

Background & Aims: Patients with pancreatic adenocarcinoma have a high incidence of diabetes, profound insulin resistance, and high circulating amylin concentrations. It was hypothesized that pancreatic cancer cells produce a factor that stimulates islets to secrete amylin but not insulin. Methods: Amylin and insulin secretion were measured after coculture of pancreatic cancer cells with β cells (BRIN-BD11). The factor responsible was characterized by exposing β cells to cancer cell–conditioned medium. Results: Coculture with pancreatic (PANC-1 HPAF, and MiaPaCa2) but not colonic cancer cells (Colo 320) significantly increased amylin secretion but did not change insulin output. This effect was both time and cell number dependent. Coculture with PANC-1 or HPAF cells significantly decreased intracellular amylin, but not insulin, content. PANC-1 or HPAF cell–conditioned medium also increased amylin secretion and decreased intracellular amylin content. The factor responsible was extracted under both neutral and acidic conditions, was heat labile, and had a molecular weight of 1500. Conclusions: A soluble factor from pancreatic cancer cells selectively stimulates amylin secretion from islet cells, explaining the excessive amylin secretion found in pancreatic cancer. Because elevation of amylin concentration is an early feature of pancreatic cancer, characterization and measurement of the tumor-derived amylin-releasing factor might be valuable in the early detection of this disease. GASTROENTEROLOGY 1998;114:130-138

Islet amyloid polypeptide (IAPP) is a 37-amino acid polypeptide coproduced with insulin in the beta-cells of the pancreatic islets. The physiological effects of IAPP have not been established. Although effects on glucose metabolism are seen only at pharmacological doses both in vitro and in vivo, effects on food intake have been shown at near-physiological concentrations. The aim of the present study was to investigate the effects of similar elevations of circulating plasma IAPP levels on glucose metabolism in rats and to evaluate the function of a novel aortic catheterization technique. In a cross-over design, two sets of experiments in which conscious unrestrained rats received chronic IAPP infusions at 0 and 2 or 0 and 7 pmol/kg min were performed. Peripheral glucose disposal was determined by means of the hyperinsulinemic euglycemic clamp technique. Chronic elevations of circulating IAPP at concentrations that reduced food intake [43.5 +/- 6.2 g (control) vs. 35.7 +/- 8.2 g (IAPP; P0.01) and 34.0 +/- 2.2 g (control) vs. 28.8 +/- 1.4 g (IAPP; P = 0.07) for the 7 and 2 pmol/kg x min experiments, respectively] had no effect on the glucose metabolic rate [GMR; 18.5 +/- 0.6 mmol/kg x h (control) vs. 18.7 +/- 0.9 mmol/kg x h (IAPP) and 14.4 +/- 0.7 mmol/kg x h (control) vs. 15.6 +/- 0.7 mmol/kg x h (IAPP) for the 7 and 2 pmol/kg x min experiments, respectively]. Thus, effects on glucose metabolism are unlikely to explain the anorectic effect of IAPP.

The diabetes or impaired glucose tolerance that occurs in most patients with pancreatic cancer is characterized by profound insulin resistance. Recent evidence suggests that the diabetes may result from the presence of the tumor rather than being a predisposing factor to development of the malignancy. Some islet hormones have been shown to exhibit diabetogenic effects. To investigate the potential role of these hormones in the diabetic state associated with pancreatic cancer, we measured islet hormones during fasting in pancreatic cancer patients (n = 30), patients with other malignancies (n = 43), and healthy controls (n = 25). Preoperative pancreatic cancer patients were classified as normal glucose tolerance (NGTT), impaired glucose tolerance (IGTT), non-insulin-requiring diabetes (NIRD), and insulin-requiring diabetes (IRD). Nine pancreatic cancer patients were studied after tumor removal by subtotal pancreatectomy. Some preoperative pancreatic cancer patients (n = 19), postoperative patients (n = 9), and controls (n = 8) were also studied during hyperglycemia and following glucagon injection. Fasting plasma C-peptide was elevated in NIRD pancreatic cancer patients compared to controls. Fasting levels of islet amyloid polypeptide (IAPP), glucagon, and somatostatin were elevated in NIRD and IRD patients. IAPP and glucagon, but not somatostatin, normalized following subtotal pancreatectomy. During hyperglycemia, increases in C-peptide and IAPP were seen only in controls and in NGTT and postoperative pancreatic cancer patients. After glucagon infusion, IAPP levels increased in controls and nondiabetic cancer patients; C-peptide levels increased in controls, nondiabetic patients, and NIRD. Responses of C-peptide and IAPP to glucagon normalized after pancreatectomy. During hyperglycemia, glucagon levels fell in all groups except IGTT patients and a decrease in somatostatin concentrations was seen in controls.

The cosecretion of insulin and islet amyloid polypeptide (IAPP) is altered when isolated rat pancreatic islets are incubated in culture media conditioned by human pancreatic cancer cells.Pancreatic cancer is usually associated with impaired glucose tolerance. This study investigates the tumor-derived influence on beta-cell secretion of pancreatic islets.Four conditioned media were prepared from two human pancreatic cancer cell lines (Panc-1 and HPAF), a hamster pancreatic cancer cell line (PC-1), and a fibroblast cell line (Ag1523). Isolated rat pancreatic islets were incubated first in the conditioned media or nonconditioned control medium for 24 h, then in the same kind of media containing 100 microM carbamylcholine for 90 min. Insulin and IAPP secretion were measured by radioimmunoassay.Islets in media conditioned by Panc-1 and HPAF cells demonstrated dissociation of insulin and IAPP secretion. During 24-h incubation, the dissociation was expressed as selectively decreased insulin secretion. With addition of 100 microM carbamylcholine, the dissociation was expressed as normal secretion of insulin and hypersecretion of IAPP. As a result, the IAPP/insulin molar ratios were increased in both groups during both time periods. The islets in PC-1 and Ag1523 media did not show any significant changes in insulin and IAPP secretion.

Rendezvous intraoperative endoscopic retrograde cholangiography (RV-IOERC), also called guidewire-facilitated IOERC, is one of the single-stage options available for managing common bile duct stones (CBDS) during laparoscopic cholecystectomy. The objective of this study is to investigate procedure-related complications in IOERC patients and stone clearance. All patients who underwent IOERC between January 2000 and December 2009 were identified from the local registry of Karolinska University Hospital in Huddinge. Medical charts and ERC reports were studied, and descriptive statistics were obtained. Outcomes were procedure-related complications, especially post-ERCP pancreatitis (PEP), stone clearance, and mortality. 307 patients were identified. In 264 of the patients, the rendezvous cannulation technique was successful (86 %); in the remaining 43 patients, conventional cannulation technique was necessary. In total, PEP occurred in seven patients (2.28 %). One of the PEP patients was in the rendezvous cannulated group (0.37 %), whereas six patients developed PEP in the nonrendezvous group (13.95 %, p

Raw soya diet in the hamster had short-term trophic effects on the pancreas, causing significant increases in pancreatic weight, DNA, RNA, and protein. These changes appear to be mediated by cholecystokinin (CCK) because the increases were blocked by infusion of the CCKA receptor antagonist, MK329. Raw soya diet significantly increased plasma levels of CCK in both the short-term and long-term studies. However, raw soya did not potentiate pancreatic cancer in hamsters treated with N-nitrosobis(2-oxopropyl)amine (BOP). Infusion of MK329 during the initiation period of carcinogenesis did not change tumor incidence or yield, suggesting that endogenous CCK does not influence tumor induction during the initiation period in the hamster.

Nine human exocrine pancreatic adenocarcinomas were examined by serial sectioning and double- and triple-labeled immunohistochemical techniques with antibodies against chromogranin A, insulin, islet amyloid polypeptide, glucagon, somatostatin, pancreatic polypeptide, serotonin, pancreastatin, and neuron-specific enolase. The results were correlated with the stage of the disease, histologic characteristics of the tumors, and survival of the patients. Cells immunoreactive with most or all of the antibodies were found in all nine cases. Abnormal co-location of some hormones in the same cell and the lack of normal co-location of other hormones were found. Endocrine cells also were identified in the invasive regions of the cancer, including perineural spaces. Abnormality in the production and release of the peptide was indicated not only in the endocrine cells of exocrine cancer, but also in the islets near the cancer. Patients whose cancer contained many endocrine cells seemed to survive longer than those with tumors containing fewer endocrine cells. The overall data suggested that the observed abnormalities may contribute to the impaired glucose tolerance found in six of these patients.

The mechanism by which high-fat diet potentiates pancreatic cancer is not known, but trophic hormones may be involved. In preliminary growth studies, hamsters fed a high fat diet (17.5% lard, 17.5% corn oil) for 14 days showed a 16.3% increase (P < 0.01) in pancreatic weight compared to controls on low fat diet (2.5% lard, 2.5% corn oil). A significant increase was also seen at 28 days. Similar increases were seen in pancreatic DNA (29%, P < 0.01) and pancreatic RNA (22%, P < 0.05) at 14 days. Plasma cholecystokinin (CCK) levels at 14 days were 2.5 fold higher in the animals fed high fat (P < 0.01). Infusion of the CCK antagonist MK329 (25 nmol/kg/h) completely abolished the increase in pancreatic weight, pancreatic DNA and pancreatic RNA. The effect of CCK receptor blockade during the initiation period of carcinogenesis was investigated in hamsters fed the same diets used in the growth studies. One hundred animals received a single injection of N-nitrosobis(2-oxopropyl)amine, (BOP, 20 mg/kg). Half of the hamsters in each diet group received a 2 week infusion of MK329 (25 nmol/kg/h), beginning 8 days before carcinogen administration. At the time of death, 55 weeks after carcinogen administration, non-fasting plasma CCK levels were 31% higher in the high fat fed hamsters than in the low fat fed animals (P < 0.01). The high-fat diet group had a 3-fold increase in total cancer incidence and a 5-fold increase in advanced lesions (adenocarcinomas). Tumor incidence and yield were not changed in either diet group by CCK-receptor blockade during the initiation period. Cholecystokinin appears to mediate the short-term trophic effect that high-fat feeding has on the pancreas. However, potentiation of pancreatic cancer by high-fat diet in the hamster cancer model does not appear to be influenced by endogenous cholecystokinin at the time of tumor induction.

Diabetes in patients with pancreatic cancer occurs in 70% to 80% of the patients and is characterized by high plasma levels of insulin. In type II diabetes that is not associated with pancreatic cancer, peripheral insulin resistance and impaired muscle glycogen synthesis are major pathogenic factors. We investigated peripheral insulin sensitivity in patients with pancreatic cancer before and after tumor removal. The effects of pancreatic tumor extracts on glycogen synthesis in skeletal muscle in vitro and the tumor content of pancreatic islet hormones were also investigated. Marked peripheral insulin resistance was found in the patients with pancreatic cancer and was more pronounced in the diabetic patients than in the nondiabetic patients. Insulin sensitivity was not correlated with weight loss, tumor size, or bilirubin levels but improved after surgery. Tumor extracts from diabetic patients with pancreatic cancer caused a marked reduction of glycogen synthesis in skeletal muscle in vitro . All tumors contained islet hormones but not in concentrations sufficient to explain the effect on glycogen synthesis. These findings indicate that a diabetogenic factor associated with pancreatic adenocarcinomas could be involved in the development of the profound peripheral insulin resistance and thereby could contribute to the high incidence of diabetes observed in patients with pancreatic cancer.

In this study, we investigated whether the anti-inflammatory drug PP56 (alpha-trinositol) may improve cancer-induced metabolic disorders. We implanted human MiaPaCa2 pancreatic cancer cells in the pancreas of 14 athymic mice for 12 weeks, using six intact littermates as normal controls. During the 12 weeks, seven tumor-cell recipients were treated with PP56 by daily injection (PPT mice). The tumor-cell recipients that were otherwise untreated were used as tumor controls (TC mice). Impaired glucose tolerance and decreased body weight gain were seen in TC but not PPT mice. When an enzyme for fatty acid beta-oxidation namely medium-chain acyl-CoA dehydrogenase (MCAD) was determined in tumor grafts; tumors from PPT mice showed more MCAD than those from TC mice. This suggests that PP56 stimulated fatty acid beta-oxidation in MiaPaCa2 cells in vivo. In keeping with this notion, PPT mice had decreased plasma free fatty acids. In vitro, we demonstrated that MiaPaCa2 cells consumed more fatty acids in the presence of PP56. In another experiment, we infused PP56 or vehicle in normal mice and found that PP56 decreased circulating glucose in the animals. We also showed that PP56 increased glucose transport in L6 skeletal muscle cells in vitro. In conclusion, PP56 increases the turnover of circulating nutrients such as glucose and helps maintain energy homeostasis in mice with pancreatic cancer.

Background Ischemia-reperfusion injury is a major concern with portal triad clamping (PTC) in liver surgery. Microdialysis allows continuous intraoperative monitoring of tissue metabolism in the liver. Our aim was to evaluate the feasibility of microdialysis as a tool to assess the intrahepatic metabolic effects of PTC in patients undergoing liver resection. Methods Eleven patients who underwent liver resection were subjected to intrahepatic microdialysis. Dialysis fluid samples were collected before, during, and after a 20-min period of PTC. Glucose, lactate, pyruvate (markers of ischemia), and glycerol (marker of cell membrane damage) were analyzed and the lactate/pyruvate ratio was calculated. Results During PTC, intrahepatic glucose, lactate, and glycerol increased from 9.1 ± 2.2 to 14.5 ± 2.4mM, from 2.2 ± 0.3 to 5.8 ± 0.5mM, and from 63 ± 14 to 142 ± 28 μM, respectively. Pyruvate was unchanged, resulting in an increased lactate/pyruvate ratio (from 39 ± 10 to 104 ± 32). During initial reperfusion, glucose further increased to 16.4 ± 2.9mM. Pyruvate increased after reperfusion (from 93 ± 18 to 138 ± 23 μM), while lactate was stable, resulting in a normalized lactate/pyruvate ratio. Glycerol continued to increase during initial reperfusion. Conclusions PTC was associated with considerable intrahepatic metabolic alterations with anaerobic metabolism, increased glycogenolysis, and cellular membrane damage resulting in increased levels of glucose, lactate, glycerol, and lactate/pyruvate ratio. Microdialysis is easy to use and allows continuous monitoring of intrahepatic metabolism during liver surgery.

The purpose of this study was to evaluate the accuracy of diffusion-weighted imaging (DWI) in diagnosis of pancreas cancer, to compare DWI with a conventional comprehensive MRI (MRI-c) and to analyse apparent diffusion coefficient (ADC) values of lesions. Thirty-six patients with pancreatic lesions (12 malignant and 24 benign) and 39 patients without lesions were included. MRI-c and DWI (free breathing, b values 0 and 500 s/mm(2)) were performed prospectively and consecutively in a 1.5-T system. The analysis was retrospectively performed blinded by two radiologists in consensus. The sensitivity, specificity, accuracy, and positive and negative predictive values of DWI and MRI-c were 92, 97, 96, 85, 98% and 100, 97, 97, 86, 100%, respectively. Mean ADC values of malignant lesions were significantly lower than those of benign lesions. DWI has a similar accuracy to MRI-c in diagnosis of pancreas cancer.

The stress response to surgery is characterized by activation of the hypothalamic-pituitary-adrenal axis and the sympathetic nervous system, and by an inflammatory response and hyperglycemia. The aim of the present study was to investigate if preoperative corticosterone could reduce the postoperative systemic stress response, without aggravating hyperglycemia or interfering with activation of the hypothalamic-pituitary-adrenal axis, in a standardized rat model of surgical trauma. We used a standardized experimental model of intestinal resection in the rat. Exogenous corticosterone (8 mg/kg body weight) or vehicle was administered 2 hours before surgery; and postoperative plasma concentrations of interleukin-6, interleukin-10, adrenaline, noradrenaline, glucose, and insulin were determined. Exogenous corticosterone decreased preoperative plasma adrenaline but did not change plasma glucose or insulin levels. Moreover, corticosterone reduced postoperative plasma interleukin-6, catecholamines, and glucose (all P < .001-.05) without any effect on the plasma corticosterone concentration compared with vehicle-treated controls. A preoperative 2-hour exposure of physiologic poststress corticosterone concentrations not only suppressed plasma IL-6 levels but also inhibited surgery-induced adrenaline release and suppressed plasma glucose levels. We hypothesize that glucocorticoids attenuated the inflammatory response in injured tissues that reduced afferent input into brain areas regulating the neuroendocrine response.

In vivo activated T lymphocytes exhibit altered expression of insulin-like growth factor-1 receptor (IGF-1R) compared to the naive T lymphocyte pool. The objective of this study was to investigate the expression of IGF-1R RNA in CD4 and CD8 positive cells after allogeneic hematopoietic stem cell transplantation (HSCT) in patients with and without GVHD. For this purpose we isolated RNA from CD4 and CD8 positive cells, sorted with immunomagnetic beads. We used real-time PCR for RNA quantification. We demonstrate a significantly decreased expression of IGF-1R RNA in both CD4 and CD8 positive cells up to 12 months after HSCT. We could not demonstrate a correlation between the IGF-1R RNA expression and T cell activating processes like GVHD, expansion of CD4 or CD8 populations or virus infections.

In the subdiaphragmatic vagal deafferentation procedure (SDA), the afferent fibers of the vagus are surgically severed unilaterally where they enter the brain stem. The technique includes a subdiaphragmal truncal vagotomy performed on the contralateral side. This procedure has been used to study the control of food intake, but it has not been used previously to investigate the role of vagal afferent fibers in the control of gastric emptying (GE). The current experiment studied the effect of SDA on the inhibition of GE by islet amyloid polypeptide (IAPP or amylin) and cholecystokinin (CCK) in awake, unrestrained rats with gastric cannulas. The experimental group underwent subdiaphragmatic vagal deafferentation; the control group had sham operations. All rats received 20-min intravenous infusions of IAPP (1, 3, 9, 27, and 81 pmol/kg/min), CCK (3, 30 and 90 pmol/kg/min), and normal saline in random order. Gastric emptying of saline was measured by the phenol red method during the last 5 min of each infusion period. CCK dose-dependently inhibited gastric emptying in both the control and SDA animals. The inhibition of GE by CCK was significantly attenuated by SDA (p0.01). IAPP also inhibited gastric emptying dose-dependently, but the difference between the SDA and control groups was not significant. The current experiment, which used a different methodology than previous studies, provides support for the hypothesis that the inhibition of gastric emptying by CCK, but not by IAPP, is mediated partly by afferent vagal fibers.

He Z, Wang F, Kumagai-Braesch M, Permert J, Holgersson J. Long-term gene expression and metabolic control exerted by lentivirus-transduced pancreatic islets. Xenotransplantation 2006; 13: 195–203. © Blackwell Munksgaard, 2006 Abstract: Background: Genetic modification of non-human islets before transplantation may provide means by which they can escape immunity and, thus, be used in a human host. To accomplish this, efficient gene transfer methods are needed. Lentiviral vectors are transgene vehicles capable of stably transducing a variety of primary, post-mitotic cells including islets. Methods: We investigated whether lentiviral transduction impaired rat pancreatic islet function long term. Following transduction, the gross morphology, viability and in vitro functionality of islets were evaluated by microscopy, adenylate nucleotide and insulin secretion assays, respectively. Further, in vivo functionality of transduced islets was assessed by transplanting the islets under the kidney capsule of diabetic nude mice. Results: All transduced islets contained green fluorescent protein (GFP)-positive cells. In single cell suspensions prepared from transduced islets, 33±8% (n=3) of dispersed islet cells were GFP-positive. The ADP/ATP ratio was 0.07±0.01 for transduced islets and 0.06±0.01 for controls (normal range

Release of glycerol and free fatty acids (FFA) was investigated in human skeletal muscle strips. In the basal state, glycerol and FFA were released at almost equimolar rates (0.3 nmol/ng tissue.90 min). A nonselective beta-adrenoceptor agonist, isoprenaline, caused a concentration-dependent stimulation of glycerol release, whereas FFA release was unaffected. Basal and isoprenaline-induced glycerol release correlated positively with the age of the donors (r = 0.5, P0.005) but not with their body mass index (Por = 0.4). Biochemical experiments with hormone-sensitive lipase (HSL) showed that most enzyme activity was both in the cytosol and mitochondrial fraction and that it constituted the common long and active form of the protein. Electron microscopy studies in rat skeletal muscle using labeled highly specific HSL antibodies verified the cytosolic location of HSL and, furthermore, indicated an accumulation of HSL-adjoining mitochondria. These results suggest that FFA produced in myocytes during catecholamine-induced lipolysis are retained by the muscle and, therefore by inference, reused. It is conceivable that efficient hydrolysis of acylglycerol by HSL located in the cytosol as well as near the mitochondria may facilitate mitochondrial FFA oxidation. In addition, muscle lipolysis activity increases during aging and may be independent of total body fat.

Hemorrhage from the pancreatic duct, i.e. hemosuccus pancreaticus (HP), is a rare cause of gastrointestinal bleeding. This potentially life-threatening complication of chronic pancreatitis may pose a significant diagnostic and therapeutic dilemma, especially in patients with silent forms of the disease.We report a case of a 64-year-old man with no history or symptoms but positive findings of chronic calcifying pancreatitis at computed tomography (CT) scan.The patient presented with repeated episodes of gastrointestinal bleeding requiring transfusion and did not, until later in the disease, develop hyperamylasemia and epigastric pain. Repeated endoscopies could not reveal the source of bleeding. The radiological diagnosis and successful transcatheter embolization of a small splenic pseudoaneurysm were performed during an interval when the patient was asymptomatic and showed no signs of bleeding.We suggest that when HP is suspected, a contrast-enhanced CT angiography with reconstruction of the arteries should be performed regardless of whether the patient shows signs of active bleeding or not.

SUMMARY The objective of this study was to investigate if oligoclonality of the Ig repertoire post-haematopoietic stem cell transplantation (HSCT) is restricted to memory B lymphocytes or if it is a general property among B lymphocytes. As a measure of B lymphocyte repertoire diversity, we have analysed size distribution of polymerase chain reaction (PCR) amplified Ig H complementarity determining region 3 (CDR3) in naive and memory B lymphocytes isolated from patients before HSCT and at 3, 6 and 12 months after HSCT as well as from healthy controls. We demonstrate a limited variation of the IgH CDR3 repertoire in the memory B lymphocyte population compared to the naive B cell population. This difference was significant at 3 and 6 months post-HSCT. Compared to healthy controls there is a significant restriction of the memory B lymphocyte repertoire at 3 months after HSCT, but not of the naive B lymphocyte repertoire. Twelve months after HSCT, the IgH CDR3 repertoire in both memory and naive B lymphocytes are as diverse as in healthy controls. Thus, our findings suggest a role for memory B cells in the restriction of the oligoclonal B cell repertoire observed early after HSCT, which may be of importance when considering reimmunization of transplanted patients.

A majority of patients with pancreatic cancer have obstructive jaundice and diabetes with skeletal muscle insulin resistance. Surgery for these patients is associated with significant morbidity. Uncoupling protein 2 (UCP2) has been proposed to regulate energy expenditure and promote liver vulnerability. The effects of obstructive jaundice on muscle glucose metabolism and expression of UCP2 in liver and muscle are unknown.Rats were operated with bile duct ligation (BDL). After 7 days, UCP2 mRNA levels were determined in liver and muscle. Simultaneously, insulin-stimulated glucose transport and glycogen synthesis in skeletal muscle were analyzed in vitro.The jaundiced rats lost more weight than pair-fed controls. UCP2 mRNA levels were increased 5-fold in liver but not in muscle in jaundiced rats compared to pair-fed controls. The jaundiced rats were hypoglycemic and hypoinsulinemic but demonstrated intact or enhanced insulin action on skeletal muscle glucose transport and glycogen synthesis in vitro. Muscle glycogen content was increased in the jaundiced rats.Experimental obstructive jaundice in the rat is associated with increased liver expression of UCP2, rapid weight loss, and intact insulin action on skeletal muscle glucose metabolism. Obstructive jaundice, by upregulated liver UCP2, may contribute to the cachexia and high surgical morbidity observed in these patients, but not to skeletal muscle insulin resistance in pancreatic cancer patients.

The discovery of a cystic lesion in the pancreas implies a challenge for the physician. Approximately 10% are cystic tumors, benign to highly malignant, or true cysts, showing all stages of cellular differentiation, from benign to highly malignant tumors. Malignant cystic tumors are rare and comprise only about 1% of all pancreatic malignancies, they are potentially curable. Therefore, correct diagnosis and treatment of these lesions are of great importance. It is usually not possible to separate a pseudocyst from a benign cyst or a cystic tumor, but there are some signs and findings that could be helpful in the clinical decision. The diagnosis of a cystic pancreatic tumor requires different imaging techniques, including ultrasonography, computerized tomography, magnetic resonance imaging, and magnetic resonance cholangiopancreatography, but to distinguish a pseudocyst or a benign cyst from a potentially malignant lesion can be very difficult. The usefulness of blood tests and investigations of cyst fluid can be questionable. Today, surgical treatment of cystic pancreatic tumors can be performed with low morbidity. Therefore, we conclude that an active strategy with resection of cystic tumors of the pancreas should be recommended.

CCK is a physiological inhibitor of gastric emptying and food intake. The pancreatic peptide amylin exerts similar actions, yet its physiological importance is uncertain. Objectives were to compare the dose-dependent effects of intravenous infusion of amylin and CCK-8 on gastric emptying and food intake in rats, and to assess whether physiological doses of amylin are effective. Amylin and CCK-8 inhibited gastric emptying with mean effective doses (ED50s) of 3 and 35 pmol · kg−1 · min−1 and maximal inhibitions of 60 and 65%, respectively. Amylin and CCK-8 inhibited food intake with ED50s of 8 and 14 pmol · kg−1 · min−1 and maximal inhibitions of 78 and 69%, respectively. The minimal effective amylin dose for each effect was 1 pmol · kg−1 · min−1. Our previous work suggests that this dose increases plasma amylin by an amount comparable to that produced by a meal. These results support the hypothesis that amylin acts as a hormonal signal to the brain to inhibit gastric emptying and food intake and that amylin produces satiety in part through inhibition of gastric emptying.

Sir, We thank the authors of this letter for their interest in our manuscript “Diffusion-weighted magnetic resonance imaging of pancreas tumours” [1] and for their valuable and interesting comments. The aim of our study was not to evaluate whether diffusion-weighted (DW)MR imaging of the pancreas can differentiate between pancreas cancer and mass-forming pancreatitis. As a part of the “Discussion” section in our manuscript, we considered it valuable to comment on the false positive findings of the comprehensive MR examination in two patients with mass-forming pancreatitis where DWI was correct in characterizing these lesions as non-malignant. Furthermore we stressed, in the “Discussion” section, that the issue of whether DW MRI can help in distinguishing between these two entities needs to be examined in studies with larger patient groups. The role of DW MRI in differentiation of pancreas cancer and massforming pancreatitis is currently a “hot topic” and there are many reports in the literature with variable results. For example, there are studies showing that ADC values of mass-forming pancreatitis are higher [2, 3] or lower [4, 5] than ADC values of pancreas cancer. Additionally, one study shows that ADC values of mass-forming pancreatitis are indistinguishable from ADC values of the remaining gland [6]. The variability of the ADC values of mass-forming pancreatitis compared with those of pancreas cancer in the aforementioned reports may be explained by the nature of inflammation in the cases of mass-forming pancreatitis, which may happen in the form of either acute relapsing pancreatitis in the setting of chronic pancreatitis that may show increased ADC values or predominant fibrosis that will reveal lower ADC values [6]. Regarding the use of the selected b value of 500 mm/s, we do agree that the T2 shine-through effect might be present, as is not the case in DW images when higher b values (800 or 1,000 mm/s) are selected. But this effect is eliminated in the corresponding ADC map [7, 8], whose use combined with the DW images with b values of 0 and 500 mm/s was a part of the evaluation in the present study. In that way, we did not encounter difficulties with the T2 shine-through effect in benign lesions in DW images with a b value of 500 mm/s. We would like to thank the authors of this letter once again for their interesting comments and express even our belief that the possible role of DW MR imaging in differentiating between pancreas cancer and massforming pancreatitis has to be thoroughly examined. This reply refers to Letter to the Editor available at http://dx.doi.org/10.1007/ s00330-010-1729-3

Islet amyloid polypeptide (IAPP) is produced in pancreatic beta cells. Intraislet function of IAPP is still uncertain. In the present study, we investigated effects of IAPP and somatostatin on stimulus-secretion coupling of beta cells in isolated rat pancreatic islets. Insulin secretion induced by 22.2 mM glucose was increased by an IAPP antiserum (0.1%) or an IAPP antagonist (IAPP8-37, 10 microM). Pretreatment of islets with pertussis toxin (PTX) abolished the stimulating effect of IAPP8-37 on glucose-induced insulin secretion. In contrast, IAPP antiserum and IAPP8-37 did not change insulin secretion induced by 30 mM KCl. Somatostatin (1 nM) inhibited insulin secretion induced by 22.2 mM glucose, 10 mM L-arginine, 25 microM forskolin, and 200 microM carbachol. IAPP (10 microM) enhanced the inhibitory effect of somatostatin on insulin secretion induced by L-arginine or forskolin. PTX pretreatment abolished the effects of somatostatin and IAPP on arginine-induced insulin secretion. In conclusion, IAPP regulates multiple steps in signal transductions of beta cells. The effects of IAPP on beta cells are mediated by PTX-sensitive regulatory G proteins.

Starvation induces an increase in intestinal permeability that can be of importance to intestinal integrity. Glutamine is the principal energy source for intestinal enterocytes and is considered essential for gut metabolism, structure and function. The aim of this study was to investigate whether glutamine could improve the ATP content of the mucosa of starved rats and attenuate the permeability perturbation during incubation in vitro in Ussing chamber.Segments of jejunum from rats starved for 48 h were mounted in Ussing chambers. Glutamine was added to Krebs-buffer at 0.6mM, 3mM, 6mM and 30mM concentrations on the mucosal side. Cr-EDTA permeation, ATP content of the epithelium mucosa and electrophysiology were studied during 180 min of incubation in Ussing chambers.These was a negative linear correlation between ATP content and(51)Cr-EDTA permeability in stripped mucosa. ATP content was reduced in all groups during the experiment. When 30 mM glutamine was added on the mucosal side there was an increase in(51)Cr-EDTA permeability (P0.001). There was no effect of glutamine on transepithelial resistance but higher concentrations of glutamine (3mM) significantly increased the short circuit current.Supplementing glutamine to the mucosal side in the Ussing chamber led to an increase in ion pump activity and to an increase in paracellular permeability at the 30mM glutamine concentration. Glutamine did not restore the intracellular ATP level. The increase in permeability was inversely correlated to the mucosal ATP content.

Introduction: Enterocyte proliferation and cellular energy status are important to intestinalintegrity after starvation and trauma. The proliferative response to nutrients is expressed in the activity of ornithine decarboxylase (ODC), but ODC activity and ATP level in the intestinal mucosa the first hours after surgery and immediate refeeding are not known. Methods: Male Wistar rats (240–280 g) were starved for 48 h and submitted to laparotomy with distalileal transection, gastrostomy and jejunal instillation of either enteral formula or saline. The ODC activity and ATP content of the jejunal mucosa were analysed in samples taken at 1, 2, 4 and 6 h after surgery. Results: ODC activity increased and reached the highest peak at 2 h in the refed animals. ATP concentrationand energy charge of jejunal mucosa were significantly reduced 6 h after surgery compared to initial levels, but there were no differences between animals that were refed or not. Intestinal transection did not stimulate ODC activity. Conclusion: ATP levels in intestinal mucosa decreased after surgery, and early enteral feeding did not seem to prevent this decrease during the first 6 h. Refeeding immediately after surgery elicits an early but transient increase of ODC activity in rat jejunal mucosa.

Abnormal insulin and islet amyloid polypeptide (IAPP) secretion are usually seen in patients with exocrine pancreatic cancer. The beta-cell dysfunction is a characteristic of the glucose intolerance found in pancreatic cancer patients. The effects of pancreatic cancer cells on insulin and IAPP secretion from beta cells are unclear. In this study, isolated rat pancreatic islets were cocultured with two human pancreatic adenocarcinoma cell lines (Panc-1 and HPAF) and a human colonic adenocarcinoma cell line (HT-29). As a control, islets were incubated in the absence of malignant cells. The accumulation of insulin and IAPP in culture media was measured by radioimmunoassay. Output of insulin and IAPP was decreased in islets cocultured with each malignant cell line. Molar ratio of secreted IAPP and insulin (IAPP/insulin) was increased in the islets cocultured with Panc-1 or HPAF cells, but not HT-29 cells. The decreased insulin and IAPP secretion were partly recovered after Panc-1, HPAF, or HT-29 cells were removed. The IAPP/insulin ratio was normalized after the removal of Panc-1 or HPAF cells. This study indicates that insulin and IAPP secretion are altered by the human adenocarcinoma cells investigated. The impairment induced by pancreatic adenocarcinoma cells is associated with a hypersecretion of IAPP relative to insulin on a molar basis.

Maintenance of intestinal integrity is essential after major abdominal surgery in malnourished subjects. The purpose of this experimental study was to investigate factors affecting small-bowel mucosa permeability in vitro in the immediate postoperative period in starved rats.Male Wistar rats were randomly placed in five groups: Controls, Anesthesia, Resection, Starvation, and Starvation + resection. Controls consisted of fed rats. Anesthesia was induced intraperitoneally with xylazine and ketamine. Resection was 5 cm of the mid-jejunum, and the starvation period was 48 h. Two hours after surgery stripped mucosal segments from the jejunum and the ileum were mounted in Ussing chambers, and the transmucosal permeation of 51Cr-labeled ethylenediaminetetraacetic acid (EDTA) and dextran (40,000 Da) was studied for 120 min while electrophysiology was monitored.Starvation increased permeability to 51Cr-EDTA in both the jejunum and ileum. In the jejunum permeability was further increased by starvation + resection. Resection or anesthesia alone did not increase permeability. The villous height in the jejunum was reduced by starvation. Mucosal permeability was correlated to the change in transepithelial resistance during experiments.Starvation was the main cause of increased mucosal permeability in both intestinal segments of the rat, but surgical trauma had an additive effect, which was most pronounced in the jejunum.

A 30-year-old previously healthy woman was diagnosed as having a vasoactive intestinal polypeptide (VIP)-producing tumour of the pancreas. Her medical history was typical for neuroendocrine gastrointestinal tumours, presenting initially with non-specific symptoms but eventually she developed life-threatening manifestations requiring intensive care due to severe dehydration. She immediately recovered following surgical resection. The patient had elevated serum concentrations of VIP as well as pancreastatin, and post-operatively elevated concentrations of three growth factors, IGF-I, EGF and TGF-alpha, were seen. The importance of the alterations in plasma concentrations of the different peptides for her symptomatology are discussed.