Summy-Long J Y, Bui V, Mantz S, Koehler E, Weisz J, Kadekaro M
Department of Pharmacology, M.S. Hershey Medical Center, Pennsylvania State University, Hershey 17033.
Neurosci Lett. 1993 Apr 2;152(1-2):190-3. doi: 10.1016/0304-3940(93)90515-m.
Intracerebroventricular (i.c.v.) administration of NG-monomethyl-L-arginine monoacetate (NMMA; 500 micrograms; 402 mM) and NG-nitro-L-arginine methyl ester (NAME; 270 micrograms; 200 mM), inhibitors of nitric oxide synthase, enhanced the rise in oxytocin but not vasopressin levels in plasma of conscious rats following 24 h of water deprivation. This effect of NMMA occurred by 10 min after administration, reached its peak at 15 min and decreased by 20 min. Daily administration of lower doses (50 micrograms and 0.5 microgram/5 microliter, i.c.v.) of another inhibitor of nitric oxide synthase, NG-nitro-L-arginine, just before and after 24 h of water deprivation and in control animals treated similarly were without effect on either vasopressin or oxytocin levels. Nitric oxide, therefore, attenuates preferentially the release of oxytocin during dehydration.
向清醒大鼠脑室内注射一氧化氮合酶抑制剂N-单甲基-L-精氨酸单乙酸盐（NMMA；500微克；402毫摩尔）和N-硝基-L-精氨酸甲酯（NAME；270微克；200毫摩尔），在禁水24小时后，可使血浆中催产素水平升高，但不影响血管加压素水平。NMMA给药后10分钟出现此效应，15分钟达到峰值，20分钟时下降。在禁水24小时前后，每天向清醒大鼠脑室内注射较低剂量（50微克和0.5微克/5微升）的另一种一氧化氮合酶抑制剂N-硝基-L-精氨酸，对血管加压素或催产素水平均无影响。因此，一氧化氮在脱水过程中优先减弱催产素的释放。
