Takata M, Zhang X, Sugimoto T, Ikeda K, Tomoda F, Mikawa M, Iida H, Mizumura Y
Jpn Heart J. 1986 Jan;27(1):95-106. doi: 10.1536/ihj.27.95.
The antihypertensive effects of intravenous injection of ketanserin, a 5-HT2 receptor antagonist, were assessed in conscious rabbits. In intact rabbits, ketanserin lowered blood pressure in a dose-dependent manner. The antihypertensive effects of ketanserin were also observed in rabbits with two-kidney, one clip (2K1C) hypertension and with one-kidney, one clip (1K1C) hypertension. The effect was more marked in the 1K1C rabbits with low plasma renin activity (PRA) and high plasma norepinephrine (PNE) than in 2K1C rabbits with high PRA and normal PNE. The heart rate was not changed. Ketanserin suppressed the pressor response to exogenous norepinephrine (0.6 micrograms/Kg) 15, 30 and 45 min after the injection of ketanserin (1 mg/Kg). It also suppressed the pressor response to phenylephrine (3 micrograms/Kg) 15 min after the injection, but it did not suppress the pressor response to angiotensin II (0.15 micrograms/Kg). In order to investigate baroreceptor function, balloons were placed around the abdominal aorta and the inferior vena cava and inflated alternately. Thus, the mean arterial pressure vs heart period-logistic curve was obtained under steady-state conditions. There were no changes after the drug administration in the range of heart period and the gain (the slope at midpoint of the curve). These results suggest that the inhibition of pressor response of norepinephrine has effects in addition to a direct vasodilatory action and that an alteration of baroreceptor function is not involved in the antihypertensive effects of ketanserin.
在清醒兔中评估了5-HT2受体拮抗剂酮色林静脉注射的降压作用。在完整兔中，酮色林以剂量依赖性方式降低血压。在二肾一夹（2K1C）高血压兔和一肾一夹（1K1C）高血压兔中也观察到了酮色林的降压作用。与血浆肾素活性（PRA）高且血浆去甲肾上腺素（PNE）正常的2K1C兔相比，血浆肾素活性低且血浆去甲肾上腺素高的1K1C兔的作用更明显。心率未改变。注射酮色林（1mg/kg）后15、30和45分钟，酮色林抑制了对外源性去甲肾上腺素（0.6μg/kg）的升压反应。注射后15分钟，它也抑制了对去氧肾上腺素（3μg/kg）的升压反应，但未抑制对血管紧张素II（0.15μg/kg）的升压反应。为了研究压力感受器功能，在腹主动脉和下腔静脉周围放置气囊并交替充气。因此，在稳态条件下获得了平均动脉压与心动周期-逻辑曲线。给药后心动周期范围和增益（曲线中点处的斜率）没有变化。这些结果表明，对去甲肾上腺素升压反应的抑制除了直接血管舒张作用外还有其他作用，并且压力感受器功能的改变不参与酮色林的降压作用。
