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Introduction Women with advanced kidney disease are advised to wait until after transplant to pursue pregnancy, but the impact of pregnancy on estimated glomerular filtration rate (eGFR) decline and kidney histology is unclear. Methods We identified a cohort of women aged 18 to 44 years at transplant from 1996 to 2014 at our 3-site program (N = 816) and determined whether they had a pregnancy >20 weeks gestation post-transplant by chart review. Outcomes included rate of change in eGFR after pregnancy, changes in kidney histology before and after pregnancy, graft failure, and 50% reduction in eGFR. Results There were 37 women with one or more pregnancies lasting longer than 20 weeks gestation post-transplant. Comparing women with and without pregnancy post-transplant, there was a significant increase in the rate of eGFR decline after pregnancy (−2.4 ml/min per 1.73 m2 per year vs. −1.9 ml/min per 1.73 m2 per year in women with no pregnancy, P < 0.001). Pregnancy did not affect the risk of graft failure, death-censored graft failure, or 50% reduction in eGFR. Conclusion Pregnancy affects the rate of eGFR decline in the allograft. Postpregnancy biopsy findings revealed an increase in vascular injury, which could be a potential mechanism. We did not find a significant increase in risk of graft failure or reduction in eGFR by 50% owing to pregnancy., Graphical abstract

The heterogeneous spectrum of kidney disease in diabetes ranges from albuminuric or non-albuminuric diabetic kidney disease to non-diabetic kidney diseases. Presumptive clinical diagnosis of diabetic kidney disease may lead to an erroneous diagnosis. Material and Method: We analyzed the clinical profile and kidney biopsy of a total of 66 type 2 diabetes patients. Based on kidney histology, they were divided into—Class I (Diabetic Nephropathy), Class II (Non-diabetic kidney disease), and Class III (Mixed lesion). Demographic data, clinical presentation, and laboratory values were collected and analyzed. This study tried to examine the heterogeneity in kidney disease, its clinical indicator, and the role of kidney biopsy in the diagnosis of kidney disease in diabetes. Results: Class I consisted of 36(54.5%), class II 17(25.8%), and class III 13(19.7%) patients. The commonest clinical presentation was nephrotic syndrome 33(50%) followed by chronic kidney disease 16(24.4%) and asymptomatic urinary abnormality 8(12.1%). Diabetic retinopathy (DR) was present in 27(41%) cases. DR was significantly higher in the class I patients (p < 0.05). Specificity and positive predictive values of DR for DN were 0.83 and 0.81, respectively (sensitivity 0.61; negative predictive values 0.64). The Association of the duration of diabetes and the level of proteinuria with DN was statistically not significant (p > 0.05). Idiopathic MN (6) and Amyloidosis (2) were the most common isolated NDKD; whereas diffuse proliferative glomerulonephritis (DPGN) (7) was the commonest NDKD in mixed disease. Another common form of NDKD in mixed disease was Thrombotic Microangiopathy (2) and IgA nephropathy (2). NDKD was observed in 5(18.5%) cases in presence of DR. We noted biopsy-proven DN even in 14(35.9%) cases without DR, in 4(50%) cases with microalbuminuria and 14(38.9%) cases with a short duration of diabetes. Conclusion: Almost half (45%) of cases with atypical presentation have non-diabetic kidney disease (NDKD), though even among these cases with atypical presentation diabetic nephropathy (either alone or in mixed form) is commonly seen in 74.2% of cases. DN has been seen in a subset of cases without DR, with microalbuminuria, and with a short duration of diabetes. Clinical indicators were insensitive in distinguishing DN Vs NDKD. Hence, a kidney biopsy may be a potential tool for the accurate diagnosis of kidney disease.

Co-intake-related interactive-synergistic influence of artemether-lumefantrine, AL and monosodium glutamate, MSG that separately mediated oxidative stress could be significant on the kidney actively involved in xenobiotic detoxification and elimination. Thus, influence of AL on rats’ kidney histomorphology and antioxidant bio-indicators following MSG-challenge was assessed. For 7 days, thirty rats (n = 5) were respectively exposed to vehicle (distilled water), therapeutic AL (TAL), high AL (HAL), MSG, MSG plus TAL or MSG plus HAL. Significant (P0.05).Rats’ kidney photomicrographs (H&E × 400) revealed normal histo-architecture in control but varied degree of fibroplasias (TAL- ,HAL- and MSG plus TAL-fed) and necrosis with infiltrations (MSG plus HAL-and MSG-fed), rats. These demonstrated MSG-related adversity and significant modulation response of TAL, unlike HAL, on the rats’ kidney histology and studied antioxidant response bio-indicators.

This study aims to determine the effect of clove syrup on creatinine, urea, and kidney histology of diabetic rats induced by streptozotocin. Eighteen male rats were divided into six groups: N, C (-), and C (+) were the control groups, and groups 1.8, 3.6, and 7.2 were the experimental groups. Groups C (-), C (+), 1.8, 3.6, and 7.2 were injected with streptozotocin 45 mg/kg BW in a single intraperitoneal injection. Normal control group or N and negative control group or C (-) were left untreated; positive control group or C (+) were treated with glibenclamide 0.09 mg/kg BW; groups 1.8, 3.6, and 7.2 were given clove syrup with doses of 1.8, 3.6, and 7.2 ml/rat/day respectively for 14 days. The obtained data were analyzed using a one-way ANOVA test, followed by the Duncan test at the significant level of 95% (a = 0.05). Kidney histology was observed by Hematoxylin-Eosin staining using Microscope. The result showed that clove syrup therapy with a dose of 3.6 ml/rat/day significantly decreases glucose, urea, and creatinine levels. Also, it showed that the dose of 3.6 has a regeneration effect to repair the damaged kidney. However, the higher amount of 7,2 ml/rat/day was toxic, causing an increase in blood glucose, urea, and creatinine levels and impairing kidney cells. In conclusion, clove syrup consumption at the right dose gave the best result in decreasing glucose, urea, and creatinine levels and regenerating the damaged kidney.

The objective of this study was to determine the description of kidney histology of Mus musculus after giving Nano Herbal Rhodomyrtus tomentosa (Haramonting). R.tomentosa (Haramonting) is made on a nanoscale using High Energy Milling (HEM). This research use the Completely Randomized Design (CRD), which consists of six groups of CMC 0.5% and Nano- R.tomentosa (Haramonting) at dosage of (100; 141,42; 200; 282,82; 400)mg/20g body weight. The kidneys were made into preparations by using the paraffin method and Hematoxylin Erlich-Eosin staining (HE). The results of histological kidneys showed that there is a significant difference (P0,05).

According to the WHO, about 3 million people die each year due to ambient air pollution. Most of the in vivo studies on the PM 2.5 effects have been done on respiratory and cardiovascular tissues. However, little is known about the effects on the tissues involved on xenobiotic removal, such as kidneys. In the present study we assess the harmful effects of sub-chronic exposure to PM 2.5 on the kidney, by investigating histologic and serum alterations in healthy and hypertensive rat models. Mean PM 2.5 concentrations during exposures were slightly above the daily WHO standard. Exposed animals showed fibrosis, mesangial expansion, decrease glomerular and tubular lumen volumes in kidneys, with an elevated BUN. Hypertensive animals also exhibited much more severe alterations than healthy animals. We conclude that PM 2.5 induces minimal or small-scale abnormalities that can be determinant for renal health preservation. Fil: Tavera Busso, Iván. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Mateos, Ana Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Juncos, Luis Isaias. Fundación J. Robert Cade; Argentina Fil: Canals, Norma. Oulton-inst D/diag y Tratamiento Ambulatorio; Argentina Fil: Carreras, Hebe Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina

In kidney transplantations, pathologists evaluate the architecture of both glomeruli, interstitium and tubules to assess the nephron status. An accurate assessment of glomerulosclerosis and tubular atrophy is crucial for determining kidney acceptance, which is currently based on the pathologists’ histological evaluations on renal biopsies in addition to clinical data. In this work, we present an automated algorithm, called RENTAG (Robust EvaluatioN of Tubular Atrophy & Glomerulosclerosis), for the segmentation and classification of glomerular and tubular structures in histopathological images. The proposed novel strategy combines the accuracy of a level-set with the semantic segmentation of convolutional neural networks to detect the glomeruli and tubules contours. In the TEST set, our method exhibited excellent performance in both glomeruli (dice score: 0.9529) and tubule (dice score: 0.9174) detection and outperformed all the compared methods. To the best of our knowledge, the RENTAG algorithm is the first fully automated method capable of quantifying glomerulosclerosis and tubular atrophy in digital histological images. The developed software can be employed for the analysis of pre-transplantation biopsies to support the pathologists' diagnostic activity.

Background Many kidneys donated for transplant in the United States are discarded because of abnormal histology. Whether histology adds incremental value beyond usual donor attributes in assessing allograft quality is unknown. Methods This population-based study included patients who received a deceased donor kidney that had been biopsied before implantation according to a prespecified protocol in France and Belgium, where preimplantation biopsy findings are generally not used for decision making in the allocation process. We also studied kidneys that had been acquired from deceased United States donors for transplantation that were biopsied during allocation and discarded because of low organ quality. Using donor and recipient characteristics, we fit multivariable Cox models for death-censored graft failure and examined whether predictive accuracy (C index) improved after adding donor histology. We matched the discarded United States kidneys to similar kidneys transplanted in Europe and calculated predicted allograft survival. Results In the development cohort of 1629 kidney recipients at two French centers, adding donor histology to the model did not significantly improve prediction of long-term allograft failure. Analyses using an external validation cohort from two Belgian centers confirmed the lack of improved accuracy from adding histology. About 45% of 1103 United States kidneys discarded because of histologic findings could be accurately matched to very similar kidneys that had been transplanted in France; these discarded kidneys would be expected to have allograft survival of 93.1% at 1 year, 80.7% at 5 years, and 68.9% at 10 years. Conclusions In this multicenter study, donor kidney histology assessment during allocation did not provide substantial incremental value in ascertaining organ quality. Many kidneys discarded on the basis of biopsy findings would likely benefit United States patients who are wait listed.

The classification of Antibody Mediated Rejection (AMR) in kidney transplant remains challenging even for experienced nephropathologists; this is partly because histological tissue stain analysis is often characterized by low inter-observer agreement and poor reproducibility. One of the implicated causes for inter-observer disagreement is the variability of tissue stain quality between (and within) pathology labs, coupled with the gradual fading of archival sections. Variations in stain colors and intensities can make tissue evaluation difficult for pathologists, ultimately affecting their ability to describe relevant morphological features. Being able to accurately predict the AMR status based on kidney histology images is crucial for improving patient treatment and care. We propose a novel pipeline to build robust deep neural networks for AMR classification based on StyPath, a histological data augmentation technique that leverages a light weight style-transfer algorithm as a means to reduce sample-specific bias. Each image was generated in \(1.84 \pm 0.03\) s using a single GTX TITAN V gpu and pytorch, making it faster than other popular histological data augmentation techniques. We evaluated our model using a Monte Carlo (MC) estimate of Bayesian performance and generate an epistemic measure of uncertainty to compare both the baseline and StyPath augmented models. We also generated Grad-CAM representations of the results which were assessed by an experienced nephropathologist; we used this qualitative analysis to elucidate on the assumptions being made by each model. Our results imply that our style-transfer augmentation technique improves histological classification performance (reducing error from 14.8% to 11.5%) and generalization ability.

The developments in the field of kidney pathology are major objectives for nephrology worldwide, since the histopathologic diagnosis is a cornerstone for all glomerulopathies (either primary or secondary related to systemic diseases-for tubulointerstitial and vascular lesions as well as renal allograft nephropathy). Moreover, the correct interpretation of kidney tissue samples is a challenge for pathologists too. Consequently, a new subspecialty - nephropathology, was accepted by many medical schools in various universities, while dedicated scientific meetings, journals and websites were also created. In the following few pages, a short overview on the history, classic and novel meanings of the renal pathology for the understanding of glomerular pathophysiology will be discussed.

Shark is a fish widespread in the tropical Indo-Pacific Ocean with a depth of 75 to 130 meters. Shark is a cartilaginous fish (Elasmobranchii). The fish is an ancient animal species that are still alive and also have different characteristics with bony fishes. Research on the histology of the shark's kidneys is still rare. The purpose of this study was to describe the histology of the shark kidneys (Carcharhinus sorrah). In this study we used one individual shark (Carcharhinus sorrah) from Depok Beach, Yogyakarta. The method used in this research was paraffin method with Hematoxylin-Eosin staining. From microscopic observation, the kidneys consist of glomerular parts, proximal tubules, distal tubules and lymphoid tissue.

Turmeric is usually consumed routinely and for a long time, so it cannot be ascertained that the use of turmeric is safe or toxic especially in the liver because there are as many as 64 compounds in turmeric which are thought to be hepatotoxic, The prevalence of preeclampsia is around 5% -15% of all pregnancies in the world, where cases of hypertension in pregnancy including preeclampsia are found in numbers that tend to increase and are the most common medical complication in pregnancy. About 70% of women diagnosed with hypertension in pregnancy are cases of preeclampsia. This study used a type of analytic research with quasi-experimental design in pregnant female rats consisting of 4 treatments with 6 replications each. This study consisted of a negative control group (k-) with only feed given ad libitum, positive control (k +) in injection of LPS intervena with a group dose of 0.2 / kgBW and a group giving turmeric extract (Curcuma longa L.) with doses of 400mg / kgBW (P1) and 600mg / kgBW (P2) respectively. After that, histological preparations were carried out on the liver of rats (Rattusnovergicus). From the results of observations of the liver morphology in the negative (-) and P2 treatment the liver color was found to be dark red, whereas in the positive control group (k +) a pale red color was found. Then histological observations showed an increase in the percentage of liver necrosis from P1 and a decrease in necrosis in P2.

Preeclampsia is a pregnancy disorder that can cause interference in the kidneys. This study aims to determine the safety effects of the combination of Nano herbal Andaliman (Zanthoxylum acanthopodium) and Extra Virgin Olive Oil (EVOO) in preeclampsia. This study consisted of 5 groups ie K(-): Pregnant Rats, K(+):PE model Rats, P1: PE model Rats + 0,45g EVOO/day/200gBW at 13rd-19th days pregnancy, P2: PE mode Rats + Nano-Andaliman 100mg/200gBW at 13rd-19th days pregnancy and P3: PE model Rats + 0,45g EVOO/day/200gBW + Nano-Andaliman 100mg/200gBW at 13rd-19th days pregnancy. This study showed no differences in kidney weight (p>0,05) but there were significant differences in Necrosis in kidneys (p < 0.05). Combination of Nano herbal Andaliman (Zanthoxylum acanthopodium) and Extra Virgin Olive Oil (EVOO) in preeclampsia can effect in histology kidneys.

Hypertension is an increase in systolic and diastolic pressure, the height of which depends on the age of the individual affected. Hypertension can also cause terminal kidney failure (GGT). One of the herbs that has the effect of reducing blood pressure is the mahkota dewa. This study aims to determine the effect of mahkota dewa extract on histological and morphological features of the kidneys in preeclampsia rat. In this study using a type of analytic research with quasi-experimental design in pregnant rat (Rattus novergicus) as many as 24 rats and consisted of 4 treatments (each treatment was divided into 6 rats). control group, P1 (pregnant rats injected by LPS) P2 (pregnant rats injected with LPS given 100 mg / BW of mahkota dewa extract once a day) and P3 (pregnant rats injected with LPS and given 200 mg/BW of deity extract twice a day). On the 17th day the pregnancies of the rat were dissected and taken by kidney organs and then made a paraffin method preparation using Hematoxylin-Eosin (HE) staining. Morphological observations showed a change in color in group K (control) = blackish red, at P1 = pale red, P2 = brownish red and P2 = thick red While the results of kidney histology on tubular narrowing and necrosis obtained significant results (P

ABSTRACT Background: Persistent hyperglycaemia results in complications in diabetes mellitus (DM) and metformin is the baseline drug used in diabetic management. The effect of metformin on fasting blood glucose (FBG), homogenized kidney tissue malonyldehyde (MDA), protein carbonyls (PCO), total antioxidant capacity (TAC) and histology in streptozotocin-induced diabetic rats was investigated. Methods: Eighteen Sprague Dawley rats were assigned into three groups (n= 6 rats per group i.e. A; negative control on distilled water, B; positive control on distilled water and C; on 100 mg/kg/day metformin groups. Diabetes mellitus (DM) was induced using streptozotocin 65 mg/kg intraperitoneally and treatments were given daily by oral gavage for 3 weeks. Plasma fasting blood glucose (FBG), kidney tissue oxidative stress markers and histology were determined. Results: The results showed that FBG, MDA, and PCO levels were significantly higher in B group compared to A group, and lower in C group compared to B. The TAC level was significantly lower in B compared to A and higher in C compared to B group of rats. However, though histological study shows improvement in kidney histology in all treatments, kidney weight did not differ. Conclution: The results suggest that, metformin reduces oxidative stress in streptozotocin-induced diabetic rats possibly through its antihyperglycaemic effect.

OBJECTIVES Scarce data exist regarding the effect of acute graft pyelonephritis on kidney histology after a kidney transplant. This study sought to assess the kidney histology at 1 month, and kidney function at 1 year, after acute graft pyelonephritis in kidney transplant patients. MATERIALS AND METHODS All kidney transplant patients with acute graft pyelonephritis between October 2006, and December 2008, underwent a kidney biopsy 1 month later (n=28). Histologic findings were compared with those observed in a control group (n=28) who underwent a protocol kidney biopsy at 1 year posttransplant and did not present with acute graft pyelonephritis. Patients were matched according to age, sex, and immunosuppressive regimen. RESULTS Kidney function was impaired by the acute graft pyelonephritis episodes at the time of biopsy. In 40% of patients, the estimated glomerular filtration rate did not return to baseline by 1 month after acute graft pyelonephritis and remained impaired thereafter. Three patients had features of acute rejection. Tubulitis was seen more frequently in the acute graft pyelonephritis group, especially in patients in whom estimated glomerular filtration rate did not completely recover by 1 month after acute graft pyelonephritis. Patients with acute graft pyelonephritis who had inflammatory infiltrate of > 20% 1 month after acute graft pyelonephritis had worse kidney function 1 year later. CONCLUSIONS After transplant, when kidney function remains impaired 1 month after acute graft pyelonephritis, kidney biopsies allowed graft rejection diagnosis and predicted kidney function recovery.

N-Acetyl-p-Aminophenol (APAP), aka acetaminophen, is the most commonly used over-the counter analgesic and antipyretic medication. However, its overdose leads to both liver and kidney damage. APAP-induced toxicity is considered as one of the primary causes of acute liver failure; numerous scientific reports have focused majorly on APAP hepatotoxicity. Alternatively, not many works approach APAP nephrotoxicity focusing on both its mechanisms of action and therapeutic exploration.Moringa oleifera(MO) is pervasive in nature, is reported to possess a surplus amount of nutrients, and is enriched with several bioactive candidates including trace elements that act as curatives for various clinical conditions. In this study, we evaluated the nephro-protective potential of MO leaf extract against APAP nephrotoxicity in male Balb/c mice. A single-dose acute oral toxicity design was implemented in this study. Group 2, 3, 4 and 5 received a toxic dose of APAP (400 mg/kg of bw, i.p) and after an hour, these groups were administered with saline (10 mL/kg), silymarin—positive control (100 mg/kg of bw, i.p), MO leaf extract (100 mg/kg of bw, i.p), and MO leaf extract (200 mg/kg bw, i.p) respectively. Group 1 was administered saline (10 mL/kg) during both the sessions. APAP-treated mice exhibited a significant elevation of serum creatinine, blood urea nitrogen, sodium, potassium and chloride levels. A remarkable depletion of antioxidant enzymes such as SOD, CAT and GSH-Px with elevated MDA levels has been observed in APAP treated kidney tissues. They also exhibited a significant rise in pro-inflammatory cytokines (TNF-α, IL-1β, IL-6) and decreased anti-inflammatory (IL-10) cytokine level in the kidney tissues. Disorganized glomerulus and dilated tubules with inflammatory cell infiltration were clearly observed in the histology of APAP treated mice kidneys. All these pathological changes were reversed in a dose-dependent manner after MO leaf extract treatment. Therefore, MO leaf extract has demonstrated some therapeutic effectiveness against APAP-induced nephrotoxicity through enhancement of the endogenous antioxidant system and a modulatory effect on specific inflammatory cytokines in kidney tissues.

Biomarker development in lupus nephritis (LN) has traditionally relied on comparing the characteristics of candidate markers to clinical findings in patients and controls from cross-sectional cohorts. In this work, two additional strategies for LN biomarker development that are gaining ground will be discussed. One approach compares analytes directly to kidney histology. The second strategy utilizes longitudinal measurements of biomarker levels at regular intervals as patients move from disease quiescence to disease flare. These approaches have begun to empower biomarkers as diagnostic and prognostic tools in LN and have revealed novel and sometimes unexpected roles for these biomarkers in the pathogenesis and prediction of LN disease activity.

Freshwater acclimatized spotted scat (Scatophagus argus) adults were adapted to 5, 10, 20 or 30 g/l seawater and observed for morphometric changes in gill and kidney histology at time points 1, 2, 10, 15 and 30 days. The overall histomorphological changes displayed by gill and kidney suggest two different phases of successful saltwater acclimation: an adaptive phase with adjustments in the abundance of gill chloride cells and renal collecting tubules, the diameter of glomerulus and collecting tubules, and the thickness of the muscular tissue of the collecting tubules; this gives way to a period with no further significant morphometric modifications.

The purpose of the study was to investigate the effect of Cadmium and selenium on blood parameters and the subsequent effect in the tissue of female rat kidney . Female rats were divided into a control group andtow experimental groups treated with Cadmium, and Cadmium +Selenium. A control and tested animals were fed with the same standard chow , but Cadmium chloride, and Cadmium+ Selenium mixture were orally gavaged daily for 28 days .At the end of the experimental period, blood samples were analyzed ,and packed cell volume ( PCV % ) , hemoglobin ( Hb ) , number of total erythrocytes count and total leucocytes count were determined . Blood analyses carried out in the present study showed that cadmium treatment causes different alterations in blood parameters as indicated by significant decrease in erythrocytes count , hemoglobin value and packed cell volume percentage as compared to control and Cd+selenium treated group . A number of histopathological change were observed in the kidney , including glomerular shrinkage, karyolysis , degenerative cell and cell necrosis at cadmium treatment and pronounced recovery after selenium cosupplemented showing a considerable antagonistic effects of Selenium + cadmium treatment . It can be concluded that the Cd exposure impair certain hematological mechanism and increase kidney tissue damage .Selenium showed beneficial effects to some extend. This study provide data on toxic effect in female rats after dietary sub lethal supplementation to heavy metals.

No Abstract. Global Journal of Medical Sciences Vol. 5(1) 2006: 41-44

Common shrews ( Sorex araneus ) were fed on earthworms containing high concentrations of lead. Both the earthworms and shrews originated from uncontaminated areas, but earthworms for the “lead” group of shrews were reared in the laboratory for 3 or 4 weeks in highly Pb-polluted soil from near an old lead smelter. The control group of shrews received the same amount of earthworms from the uncontaminated area. The acceptance of the experimental food by shrews was significantly lower in the lead group; indicating that the shrews were able to detect the lead in their food. After 2 – 31 days of feeding, the shrews in the lead group had significantly higher Pb concentrations in their liver, kidney, bone, and pelt than did the controls. Both the number of deaths during the experiment and the proportion of individuals with changes in kidney histology were significantly higher in the lead group.

We report on five 6-month experiments during which five colonies of four male and four female rats were exposed to psychosocial stress. Monthly blood pressure measurements by a tail-cuff method showed a modest (10 mm Hg) increase in two studies using Sprague-Dawley rats. In two further studies using the more aggressive Long-Evans strain, terminal direct carotid arterial pressures were taken as well, and in one study the differences exceeded 20 mm Hg. A fifth study used the Wistar-Kyoto, hyperactive (WKHA) strain developed by Hendley, and no differences were observed. Heart and adrenal weights; adrenal catecholamine synthetic enzymes; and heart, aortic, and kidney histology were measured and showed significant changes, which for the most part paralleled blood pressure changes. Social instability and the associated blood pressure changes were made more severe by periodic mixing of males from different colonies. This had no effect on the peaceable WKHA rats, some effect on the Sprague-Dawley rats, and a severe effect on the Long-Evans rats. The WKHA rats failed to show blood pressure changes despite stress-induced increases in heart and adrenal weights. Thus, different types of psychosocial stress and different genetics combine to induce a variety of neuroendocrine changes, not all of which necessarily lead to increased blood pressure.

Spontaneous aging changes in the kidneys of the rat have been previously described. In the Lewis strain, we performed semiquantitative studies of kidney histology and quantitative studies of glomerular basement membrane thickness and mesangial area in animals aged 6–30 months. There is a progressive increase in glomerular basement membrane thickness and mesangial area throughout the life of the rat. Spontaneous glomerulosclerosis in the Lewis rat does not appear to be as extensive as in other strains. The importance of spontaneous glomerulosclerosis in studies of induced kidney disease is emphasized.

Antibody-mediated injury to proximal tubules in Heymann nephritis. To evaluate the hypothesis that antibody-mediated damage to proximal tubules (PT) could be a feature of Heymann nephritis (HN), we studied the kidneys of rats in different stages of the disease by light, immunofluorescence (IF), transmission, and scanning electron microscopy. The observations of morphology were correlated with titers of circulating antibodies directed against the brush border (BB) and with proteinuria. Antibody titers reached a maximum 5 to 7 weeks after immunization with Fx1A, coincident with the onset of proteinuria. IgG and C3 were deposited along the BB of PT in all animals within the first week of proteinuria. BB antibodies were present in the urine of those rats. As antibody titers declined, a decrease in the extent of in vivo IgG deposition along the BB was also noted. The results of indirect IF tests, by using BB antibodies on kidneys of rats with HN of 3 to 4 months' duration, suggested extensive loss of the BB antigen(s) from the PT. Numerous granular deposits of IgG were present along the basement membrane of PT at that time. Study of kidney histology revealed that deposition of IgG and C3 along the BB of PT was associated with extensive loss of microvilli, as well as degeneration and proliferation of PT cells. Subepithelial electron-dense deposits were present along the basement membrane of PT. In rats with HN of more than 4 months' duration, with little or no circulating BB antibodies and persistent proteinuria, IgG and C3 were found in minimal amounts along BB. Examination by light and electron microscopy provided evidence of partial recovery of PT lesions in those kidneys. Rats with similar proteinuria resulting from chronic serum sickness did not have similar abnormalities of PT. These observations are consistent with the interpretation that, in rats with HN, BB antibodies induce cytotoxic injury to PT. Lesions des tubules proximaux a mediation par anticorps dans la nephrite de Heymann. Pour evaluer l'hypothese selon laquelle des lesions des tubes proximaux (PT) ayant des anticorps comme mediateurs pourraient etre une caracteristique de la nephrite de Heymann (HN), des reins de rats a differentes etapes de la maladie ont ete etudies en microscopie photonique, d'immunofluorescence (IF), electronique a transmission, et a balayage. Les observations morphologiques ont ete correlees avec les titres d'anticorps circulants diriges contre la bordure en brosse (BB) et avec la proteinurie. Les titres d'anticorps ont atteint un maximum 5 a 7 semaines apres l'immunisation avec Fx1A, en coincidence avec l'installation de la proteinurie. IgG et C3 etaient deposes le long de BB du tube proximal chez tous les animaux dans la premiere semaine de la proteinurie. Des anticorps anti BB etaient presents dans l'urine de ces rats. Au fur et a mesure que les titres d'anticorps ont baisse, il a ete observe une diminution des depots d'IgG in vivo le long de BB. Les resultats des tests IF indirects, utilisant des anticorps anti BB sur les reins de rats atteints de HN depuis 3 a 4 mois, suggerent une perte importante des antigene(s) de BB du tube proximal. De nombreux depots granulaires d'IgG sont observes le long de la membrane basale du tube proximal a ce stade. L'etude de l'histologie renale revele que le depot d'IgG et de C3 le long de BB du tube proximal est associe a une perte importante de microvillosites et a la degenerescence et la proliferation des cellules du tube proximal. Des depots denses sous-epitheliaux ont ete observes le long de la membrane basale du tube proximal. Chez les rats atteints de HN depuis plus de 4 mois, avec peu ou pas d'anticorps anti BB circulants et une proteinurie persistante, de l'IgG et du C3 ont ete observes en quantites faibles le long de BB. L'examen en microscopie photonique et electronique a montre des signes de recuperation partielle des lesions du tube proximal. Les rats ayant une proteinurie semblable, consequence d'une maladie serique chronique, n'ont pas ces anomalies du tube proximal. Ces observations sont compatibles avec l'interpretation selon laquelle chez les rats atteints de HN les anticorps anti BB produisent des lesions cytotoxiques du tube proximal.

Histological studies on kidney of rainbow trout individuals reared in freshwater ponds prior to their release into the Baltic as well as of those kept for several weeks in tanks filled with fresh and Baltic water revealed a reduction in number and size of Malpighi bodies, smaller lumen of renal tubules, and a lymphoid tissue proliferation in kidney parenchyma to have occurred in fishes dwelling in sea water.