摘要
本研究在大鼠离体右心房制备标本上观察新型抗高血压药Ketanscnn(Ket)对心率的直接作用和探讨其可能的机理。发现:Ket累积给药(0.1～300μmol/L)产生明显的剂量依赖性的负性频率作用,PD_2=48;阿托品30 nmol/L不影响Ket的负性频率作用;Ket 1.5 μmol/L不明显影响异丙肾上腺素正性频率作用的量-效曲线,但能使5-羟色胺(5-HT)正性频率作用的量—效曲线右移。提示Ket的负性频率作用与其拮抗窦房结5-HT_2受体有关,而与β-受体和M-胆碱能受体无关。
The direct effect of Ketanserin (Ket) on heart rate and its mechanism were studied using isolated male Sprague-Dawley rat right atria. Ket (0.1-300μmol/L) produced apparent negative chronotropic action in a dose-dependent manner, the pD2 value was 4.8. Atropine (30 nmol/L) did not affect the negative chronotropic action of Ket Differing from the β-receptor blocking agent propfanoloi (1μmol/L), Ket (1.5μmol/L) did not change the positive chronotropic dose-response curve for isoprenaline, but shifted the positive chronotropic dose-response curve for 5-hydroxytryptamine to the right and depressed its maximal response. These results indicate that the negative chronotropic action of Ket was related to the blockade of the 5-HT2-serotonergic receptor in the sinus node of rat atria, whereas the β-adrenoreceptor and M-cholinergic receptor were not involved in the negative chronotropic action of Ket
出处
《第二军医大学学报》
CAS
CSCD
北大核心
1990年第5期397-400,共4页
Academic Journal of Second Military Medical University
关键词
KETANSERIN
离体心房
心率
Ketanserin
isoproterenol
5-bydroxytryptamine
atropine
dose-response curve
isolated atrium
heart rate
