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Abnormal islet microcirculation impetus the insulin production and accelerates progression of Type 1 and 2 diabetes. In this study, we investigated whether tetramethylpyrazine phosphate (TMPP), a vasoactive substance, could regulate the islet microcirculation and insulin concentration and improve glycaemia in SD rats. SD rats were randomly divided into two groups, the control and TMPP groups. Each group was further divided into three subgroups according to the intravenous injection of either saline, 15 or 30% glucose. The non-radioactive microsphere technique was adopted to measure the organ blood flow. Nitric oxide synthase (NOS) blocker l-NAME was used to address whether NO was involved in mediating the vasoactive effects of TMPP. In the TMPP group, TMPP increased the PBF (pancreatic blood flow), IBF (islet blood flow), and fIBF (fraction of islet blood flow out of pancreatic blood flow) by 57, 76 and 47%, respectively, after 30% glucose infusion, compared with the control, indicating that TMPP could regulate islet microcirculation. Furthermore, TMPP induced a 66% elevation of IBF and 37% of fIBF in the 30% glucose subgroups than the 15% ones. In 30% glucose-treated subgroups, TMPP improved the blood glucose concentration by 10%, compared with the control (19.3 ± 0.64 vs 17.32 ± 0.56 mmol/l, P

42 cases of hypertensive encephalorrhagia (HER) were randomly divided into two groups. All cases received treatment within three days after the attack, group I received current conventional treatment as control, group II took 100ml Naoxuenin (NXN) oral liquid with conventional treatment. Effects were evaluated after 14-day treatment. Results indicated that NXN had direct therapeutic effect or/and synergistic effect on HER in acute phase, the mortality was significantly lowered (P0.05) and the recovery of nerve function speeded up in group II. And NXN displayed similar effect on different Syndromes and Types of the acute phase of HER (P0.05). Analysis of results of hemorheological examination of pre- and post-treatment suggested that NXN could improve the microcirculation and prevent the high hemo-viscosity syndrome caused by dehydration therapy.

In mice, DMPS (250 mg/kg, i.v.) combined with diazepam (1.25 mg/kg, i.p.) could increase LD50 of p. o. SCD 5.3 times. DMPS (62.5 mg/kg, i.v.) antagonized completely the respiratory depression and neuromuscular blockade caused by SCD(7.5 mg/kg, i.v.) in rabbits. SCD (15 mg/kg, i.v.) caused tremor, tonic convulsion and the abnormal paroxysmal discharges in EEG in rabbits. DMPS (0.5 mg/kg, i.c.v) could not eliminate the abnormal paroxysmal discharges in EEG of rabbits. DMPS (62.5 mg/kg, i.v.) combined with diazepam (5 mg/kg, i.v.) completely and rapidly antagonize these toxic symptoms and the abnormal changes in EEG.

Methyl methanesulfonate (MMS 75 mg.kg-1)-induced unscheduled DNA synthesis (UDS) was inhibited significantly in the spermatozoa of mice injected with Poly I-C (0.05, 0.50, and 5.00 mg.kg-1) at 4 h prior to ip MMS. Radioactivity was reduced from 53 +/- 3 to 50, 45 +/- 5, and 34 +/- 6 dpm/million sperms respectively. The effects of Poly I-C were dose-dependent (r = 0.9498, P less than 0.05) in inhibition of MMS-induced UDS. The effect of serum collected from the mice injected with Poly I-C (0.50 mg.kg-1) had similar effects as that of Poly I-C. Our findings suggest that both Poly I-C alone and mouse serum induced with Poly I-C may prevent the DNA damage produced by MMS.

Effects of Ca2+ and calcium antagonists nicardipine (Nic) and chlorpromazine (CPZ) on the proliferation, DNA synthesis and intracellular calmodulin (CaM) levels in cultured rabbit aortic smooth muscle cells were investigated. Maximal response of cell to Ca2+ stimulation occurred in the normal medium with CaCl2 1.4 mmol/L, whereas CaCl2 0.02-0.6 mmol/L, Nic (2.5-40.0 mumol/L) and CPZ (5.0-20.0 mumol/L) inhibited the cell proliferation in a concentration-dependent manner. The additive effects of Nic and CPZ were observed. There was a transient surge of intracellular soluble CaM level at 9h in late G1 phase of the cell cycle just before the initiation of DNA synthesis. Not only the initiation of DNA synthesis but also the CaM surge were prevented by adding Nic or CPZ (20-40 mumol/L) to media. These results suggest that an appropriate extracellular Ca2+ concentration was required for aortic smooth muscle cells to grow normally. Since calcium antagonists influenced the intracellular Ca2+ pool by blockade of calcium channel and they inhibited the CaM function directly by anticalmodulin activity or indirectly through altered intracellular Ca2+ metabolism, intracellular Ca2+ and CaM levels may be involved in the effects of Nic and CPZ on the proliferation and DNA synthesis.

This paper reports the effect of SO2 on rat nasal mucosa. The rats were forced to inhale SO2 and the effect on the nasal mucosa observed. The rats were divided into four groups. The first group inhaled 10ppm SO2; the second group 20ppm; the third group 40 ppm and the fourth group served as control. The observation lasted for 6 months. It was found that the nasal mucosa in the control group remained columnar ciliated. In the experimental groups, during the early stage (groups I, II) of exposure, there was no significant morphological change in epithelium. Then (groups I, II) the epithelium changed into cuboidal with complete disappearance of cilia, only some short and slender microvilli remained. While in the late stage (group III), the epithelium had transformed into squamous stratified and the amount of mucosal glands reduced.