大鼠缺氧性肺、脑血管反应中钾通道的作用

The Role of K￣+ Channels in Hypoxic Pulmonary and Cerebral Vascular Responses in Rats

通过实验研究不同类型的Ｋ￣＋通道阻滞剂４－氨基吡啶（４－ＡＰ）、优降糖和ＡＴＰ敏感Ｋ￣＋通道开放剂ＷＡＹ－１２０４９１对大鼠在体缺氧性肺、脑血管反应的影响，以探讨Ｋ￣＋通道在其中的作用。结果，４－ＡＰ能明显增强缺氧性肺血管收缩反应（ＨＰＶ），减弱缺氧性脑血管扩张反应（ＨＣＶＤ）；ＷＡＹ－１２０４９１能减弱ＨＰＶ，对ＨＣＶＤ无作用；优降糖对ＨＰＶ及ＨＣＶＤ均无影响。提示，４－ＡＰ敏感的钾通道开放参与ＨＰＶ和ＨＣＶＤ，可能调节ＨＰＶ，而介导ＨＣＶＤ；ＡＴＰ敏感Ｋ￣＋通道的阻滞可能介导ＨＰＶ。

The effects of different K￣+ channel blockers 4-aminopyrimide(4-AP),glibenclamide and ATP sensitive K￣+channel opener WAY-120491 on hypoxic responses of pulmonary and cerebral blood vessels were studied.The results showed:4-AP potentiated hypoxic pulmonary vasoconstriction(HPV)and lessened hypoxic cerebral vasodilation (HCVD)significantly.WAY-12049 lessened HPV,but had no effect on HCVD.Glibenclamide had no effect on HPV and HCVD. This suggests that 4-AP sensitive K￣+ channel is involved in HPV and HCVD,its activation might modulate HPV but mediate HCVD. Inhibition of ATP sensitive K￣+ channel might mediate HPV. Its role in HCVD is uncertain.