5—羟色胺和其它活性物质对肺血管的相互作用及有关阻断剂的影响

INTERACTION OF 5-HYDROXYPTAMINE AND OTHER VASOACTIVE AGENTS ON GUINEA-PIG PULS VESSELS AND EFFECTS OF THE ANTAGONIST CONCERNED

本文采用豚鼠离体肺动脉环的方法,观察了5—羟色胺(5-HT)、去甲肾上腺素(NA)及组织胺(Hist)对肺血管的作用。结果表明,5—HT除可直接引起肺动脉收缩外,其在0.024μmol/L及0.03μmol/L浓度时即可明显加强NA及Hist对肺动脉的收缩作用。5-HT_2受体特异性阻断剂Ketanserin在不影响NA和Hist作用的浓度时即可完全阻断5-HT对NA和Hist的加强作用,提示5-HT的加强作用和血管的5—HT_2受体有关。茛菪类药物阿托品可竞争性地阻断NA和Hist对肺动脉的收缩作用,可能是其治疗肺微循环障碍性疾病有效的原因之一。但对5-HT引起的肺血管收缩,阿托品无阻断作用或有增强效应。

The effects of 5-Hydroxyiryptamine(5-HT),noradrenaline (NA)and histamine (Hist) on pulmonary vessels were studied in guinea-pig isolated main pulmonary arterial rings in this paper.The results show that 5-HT, in addition to causing vasoconstriction, could potentiate the vasoconstrictor responses induced by NA and Hist.This effect could be blocked by ketanserin suggests that the potentiation of 5-HT to NA and Hist may be associated with 5-HT2 serotonergic receptor.Atropine could block competitively the vasoconstrictor responses of NA and Hist, the pA_2 values of atropine are 5,24±0.14 and 5.77±0.16,respectively.However, the pulmonary artery contraction induced by 5-HT is unaffected or amplified by various concentration of atropine.