GABA能中间神经元在外侧下丘脑降压反应中的作用

目的：分析外侧下丘脑（LH）降压反应的机制。方法：大鼠脑内或静脉注射不同药物，观察血压和心率的变化。结果：L-谷氨酸（Glu）兴奋LH引起的降压反应可被酚妥拉明、心得安或甲基阿托品（i．v．）衰减，也可被延髓头端腹外测区（RVL）内分别注射酚妥拉明、心得安、阿托品或GDEE（Glu拮抗剂）削弱。进一步的实验显示LH降压区内预先注射GABA受体阻断剂荷包牡丹碱可反转Glu兴奋该区引起的降压反应。结论：Glu兴奋LH降压区可能通过其内的GABA能中间神经元抑制LH升压反应而产生降压效应。

ROLE OF GABA-ERGIC INTERNEURONS IN LATERAL HYPOTHALAMUS DEPRESSOR RESPONSE

Objective: Analysis of mechanisms underlying depressor response of lateral hypothalamus (LH). Methods: Effects of different drugs delivered by i. v. or intra-brain injections on blood pressure and heart rate were observed. Results: The depressor response of the LH to glutamate (Glu)could be attenuated by phentolamine ,propranolol or methyl atropine (i. v. ), and could also be reduced by intra-RVI, (rostral ventrolateral medulla ) microinjection of either phentolamine, propranolol, atropine or GDEE (a Glu antagonist) ;and further experiments revealed that bicuculline (a GABA recepter blocker) preinjection into bilateral LH-depressor region could reverse the LH-depressor response. Conclusion:The LH depressor response may be due to the inhibition of the LH pressor response by GABAergic interneurons in LH.