孤束核内大剂量注射地塞米松快速引起心血管活动降低  

RAPID VASODEPRESSION INDUCED BY LARGE DOSAGE OF DEXAMETHASONE INJECTED INTO THE NUCLEUS TRACTUS SOLITARIUS

作　　者：欧阳明[1] 王绍[1] 

机构地区：[1]白求恩医科大学生理教研室,长春130021

出　　处：《动物学报》1999年第3期311-316,共6页ACTA ZOOLOGICA SINICA

摘　　要：分别将不同剂量的地塞米松注射到大鼠内侧和中间内侧孤束核，观察心血管活动的变化．结果发现：小剂量地塞米松（20或50ng）对心血管活动无明显的影响（P＞0．05），大剂量地塞米松（100或250ng）注射后10分钟内能使心血管活动明显降低（100ng：－1．80±0．32kPa，－31±13b．／min；250ng：－2．68±0．51kPa，－44±15b．／min；P＜0．01）。不仅如此，小剂量地塞米松（20ng）注入孤束核后对血清中亚硝酸根离子浓度无明显的影响（P＞005），大剂量地塞米松（250ng）可使血清中亚硝酸根离子浓度显著升高（19．33±0．29μmol／L，vs．control8.26±0.26μmol／L,P＜0.05）。这些结果提示大剂量地塞米松在孤束核内可能通过非基因调控机制捉进外周一氧化氮的形成达到调节心血管活动的作用。Changes of cardiovascular action were observed after different doses of dexamethasone (Dex) were microinjected into the medial and intermediate part of the nucleus tractus solitarius (NTS). It was found that there were no significant variations in cardiovascular action and serum nitrite concerntration after small dosage of Dex (20 or 50 ng/0. 1μl)administrated into the mediate and intermediate of NTS (P>0. 05), but microinjection of large dosage of Dex (100 or 250 ng/μl) into the same area markably decreased the cardiovascular action within 10 minutes (Dex 100 ng: - 1. 80±0. 32 kPa, - 31 ±13 b. /min, P<0. 05 or Dex 250ng: -2. 68±0.51 kPa, -44±15 b. /min, P<0. 01)-. Moreover, serum nitrite concentration was increased significantly after large doses of Dex was microinjected into the mediate and intermediate of the NTS (19. 33±0. 29μmol/L, vs. control 8. 26±0. 26μmol/L, P<0. 05). It suggests that microinjection of large doses of Dex into the NTS might enhance the serum nitric oxide formation to modulate the cardiovascular action by non-genomic mechanism.

关 键 词：地塞米松 孤束核 心血管活动 一氧化氮 

分 类 号：Q577[生物学—生物化学] R977.11[医药卫生—药品]