ABSTRACT
<p><b>INTRODUCTION</b>Diabetes mellitus induces microangiopathic changes that lead to endothelial dysfunction. This study investigated the effect of Xiaokening, a type of Chinese compound medicine, on the mesenteric arteriolar endothelial cell function of diabetic rats and its underlying mechanism.</p><p><b>METHODS</b>Diabetes mellitus was induced in rat models via intraperitoneal injection of 60 mg/kg streptozotocin and observed over three weeks. Mesenteric arterioles, which were isolated in a cannulated and pressurised state, were incubated with intravascular injections of 1, 3 or 5 g/L Xiaokening for 24, 48 or 72 hours. The effects of Xiaokening on the release of nitric oxide (NO) on the mesenteric arterioles were detected under shear stress of 1, 10 and 20 dyn/cm(2). Biochemical methods were used to determine the activities of superoxide dismutase (SOD) and xanthine oxidase (XO). The expressions of endothelial NO synthase (eNOS), SOD and XO in the mesenteric arterioles were assessed using Western blot.</p><p><b>RESULTS</b>Compared to normal rat arterioles, less NO was released in the mesenteric arterioles of diabetic rats. Xiaokening was found to have a concentration- and time-dependent effect on NO release; when the shear stress was increased, there was a gradual increase in the release of NO. Compared to normal arterioles, the expression of eNOS in the mesenteric arterioles of diabetic rats was lower. Incubation with Xiaokening increased SOD activity and expression, and decreased XO activity and expression in the mesenteric arterioles of the diabetic rats.</p><p><b>CONCLUSION</b>Xiaokening was able to significantly increase NO release and improve the endothelial function of mesenteric arterioles through antioxidative mechanisms.</p>
Subject(s)
Animals , Male , Rats , Antioxidants , Chemistry , Arterioles , Diabetes Mellitus, Experimental , Drug Therapy , Dose-Response Relationship, Drug , Drugs, Chinese Herbal , Pharmacology , Endothelial Cells , Injections, Intraperitoneal , Nitric Oxide , Metabolism , Nitric Oxide Synthase Type III , Metabolism , Oxygen , Metabolism , Rats, Sprague-Dawley , Streptozocin , Superoxide Dismutase , Metabolism , Xanthine Oxidase , MetabolismABSTRACT
AIM: To investigate the role of the nucleus tractus solitarius (NTS) in the regulation of paraventricular nucleus (PVN) AVP-ergic neurons on gastric ischemia- reperfusion injury (GI-RI). METHODS: Male SD rats were used in experiments. The celiac artery were clamped for 30 min and reperfused 1 h by removal of the clamp to obtain the ischemia-reperfusion state. The mechanism was analysed with nucleus electrical stimulation, electrolytic lesion and nucleus microinjection technique. RESULTS: Microinjection of arginine-vasopressin (AVP) into PVN obviously attenuated the GI-RI and dose-dependent effects were observed ( r= -0.477, P
ABSTRACT
AIM: To determine the effect of electrical stimulation of lateral hypothalamic area(LHA) on gastric ischemia-reperfusion injury(GI-RI) in rats and to analyse its possible neuroregulatory mechanisms. METHODS: The methods of electrical stimulation(ES), chemical stimulation, electrolytic lesion(EL) and denervation were used to investigate the effect of LHA ES on gastric mucosal injury in rats subjected to 30 min gastric ischemia followed by 60 min reperfusion and to analyse the role of dorsal vagal complex(DVC), vagus and sympathetic nerve in this effect. RESULTS: ①Electrical stimulation of LHA and microinjection of L-glutamic acid into LHA obviously aggravated GI-RI; ②Electrolytic lesion of the LHA attenuated the GI-RI;③DVC lesion eliminated the effect of electrical stimulation of LHA on GI-RI; ④Vagotomy or sympathectomy eliminated the effect of electrical stimulation of LHA on GI-RI too.CONCLUSION: These results indicate that the LHA is a specific area in the CNS for exerting aggravative effects on the GI-RI; the DVC, vagus and sympathetic nerve may be involved in regulatory effects of LHA on GI-RI.