Hatake K, Wakabayashi I, Taniguchi T, Hishida S
Department of Legal Medicine, Hyogo College of Medicine, Japan.
Alcohol Clin Exp Res. 1994 Aug;18(4):1018-23. doi: 10.1111/j.1530-0277.1994.tb00076.x.
We investigated the mechanism underlying increased relaxation of aortic strips to acetylcholine in rats chronically treated with ethanol. Rats were divided into three groups and maintained on liquid diets containing ethanol (35% of total calories) as the ethanol-fed group or an equicaloric volume of sucrose instead of ethanol as the sucrose-fed group for 10 weeks. The control group was also maintained on modified American Institute of Nutrition diet for the same period. Vascular strips of isolated rat aortas were mounted in organ chambers to record isometric tension. The endothelium-dependent relaxation responses to acetylcholine and calcium ionophore A23187 were greater in ethanol-fed rats than in control and sucrose-fed rats. However, the relaxation response to sodium nitroprusside or nifedipine did not differ among the three groups. Acetylcholine, calcium ionophore A23187, and sodium nitroprusside caused an increase in the cGMP contents of rat aortic strips that was similar among the three groups. These results suggest that a cGMP-independent relaxation mechanism is involved in the increased relaxation response to acetylcholine after chronic treatment with ethanol.
我们研究了长期用乙醇处理的大鼠主动脉条对乙酰胆碱舒张反应增强的潜在机制。将大鼠分为三组，分别给予含乙醇（占总热量的35%）的液体饮食作为乙醇喂养组，或给予等热量的蔗糖而非乙醇作为蔗糖喂养组，持续10周。对照组在同一时期给予改良的美国营养学会饮食。将分离的大鼠主动脉血管条安装在器官浴槽中记录等长张力。乙醇喂养大鼠对乙酰胆碱和钙离子载体A23187的内皮依赖性舒张反应比对照组和蔗糖喂养大鼠更强。然而，三组对硝普钠或硝苯地平的舒张反应没有差异。乙酰胆碱、钙离子载体A23187和硝普钠使大鼠主动脉条中的cGMP含量增加，三组情况相似。这些结果表明，在用乙醇长期处理后，对乙酰胆碱的舒张反应增强涉及一种不依赖cGMP的舒张机制。
