【摘要】 目的：研究糖皮质激素对去甲肾上腺素在孤束核对心血管活动调节的影响．方法：向内侧和中间内侧孤束核（ＮＴＳ）微量注射地塞米松（Ｄｅｘ）、去甲肾上腺素（ＮＥ）、米非司酮及荷包牡丹碱（Ｂｉｃ），观察它们引起的心血管活动的变化．结果：Ｄｅｘ（０３９ｍｍｏｌ·Ｌ－１，０１μＬ）可以消除１０ｍｉｎ后在同一区域注射ＮＥ（８ｍｍｏｌ·Ｌ－１，０１μＬ）所引起的血压下降、心率减慢的效应，这种抑制作用４ｈ内不消失．其中的快速抑制作用不能被米非司酮（４６６μｍｏｌ·Ｌ－１，０１μＬ）所拮抗，但可以被Ｂｉｃ（３２４μｍｏｌ·Ｌ－１，０１μＬ）所阻断．结论：Ｄｅｘ消除ＮＥ在ＮＴＳ内引起的心血管效应，其机制可能通过ＧＡＢＡＡ受体来介导．更多还原

【Abstract】 AIM: To study the effect of dexamethasone on cardiovascular response induced by nore￣pine￣phrine (NE) in nucleus tractus solitarii (NTS). ME￣THODS: The variations of cardiovascular action caused by these drugs were observed after injection of mifepristone (Mif), dexamethasone (Dex), bicuculline (Bic), and NE into the medial and intermediate NTS. RESULTS: Microinjection of Dex (0 39 mmol·L -1 , 0 1 μL) into the medial and in￣ter￣mediate NTS abolished the vasodepressed response to NE (8 mmol·L -1 , 0 1 μL) micro￣injected into the same area 10 min later, and the inhibition did not disappear until 4 h. The rapid inhibitory effects of Dex on NE vasodepression was not antagonized by Mif (4 66 μmol ·L -1 , 0 1 μL ), but it was blocked by Bic (3 24 μmol·L -1 , 0 1 μL). CONCLUSION: Dex abolished cardiovascular response to NE microinjected into NTS which may be mediated by GABA A receptor.更多还原