Inoue M, Crofton J T, Share L
Department of Physiology and Biophysics, University of Tennessee, Memphis 38163.
Am J Physiol. 1991 Aug;261(2 Pt 2):R420-6. doi: 10.1152/ajpregu.1991.261.2.R420.
We have examined in conscious rats the interaction between centrally acting prostanoids and acetylcholine in the stimulation of vasopressin secretion. The intracerebroventricular (icv) administration of carbachol (25 ng) resulted in marked transient increases in the plasma vasopressin concentration and mean arterial blood pressure and a transient reduction in heart rate. Central cyclooxygenase blockade by pretreatment icv with either meclofenamate (100 micrograms) or indomethacin (100 micrograms) virtually completely blocked these responses. Prostaglandin (PG) D2 (20 micrograms icv) caused transient increases in the plasma vasopressin concentration (much smaller than after carbachol) and heart rate, whereas mean arterial blood pressure rose gradually during the 15-min course of the experiment. Pretreatment with the muscarinic antagonist atropine (10 micrograms icv) decreased the peak vasopressin response to icv PGD2 by approximately one-third but had no effect on the cardiovascular responses. We conclude that the stimulation of vasopressin release by centrally acting acetylcholine is dependent on increased prostanoid biosynthesis. On the other hand, stimulation of vasopressin release by icv PGD2 is partially dependent on activation of a cholinergic pathway.
我们在清醒大鼠中研究了中枢作用的前列腺素与乙酰胆碱在刺激血管加压素分泌方面的相互作用。脑室内（icv）注射卡巴胆碱（25 ng）导致血浆血管加压素浓度和平均动脉血压显著短暂升高，以及心率短暂降低。预先经icv给予甲氯芬那酸（100微克）或吲哚美辛（100微克）进行中枢环氧化酶阻断，几乎完全阻断了这些反应。前列腺素（PG）D2（icv注射20微克）导致血浆血管加压素浓度短暂升高（比卡巴胆碱作用后小得多）和心率升高，而在实验的15分钟过程中平均动脉血压逐渐升高。预先用毒蕈碱拮抗剂阿托品（icv注射10微克）处理，可使对icv PGD2的血管加压素峰值反应降低约三分之一，但对心血管反应无影响。我们得出结论，中枢作用的乙酰胆碱刺激血管加压素释放依赖于前列腺素生物合成增加。另一方面，icv PGD2刺激血管加压素释放部分依赖于胆碱能途径的激活。
