Takahara Akira, Iwasaki Hiroshi, Nakamura Yuji, Sugiyama Atsushi
Department of Pharmacology, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Chuo, Yamanashi 409-3898, Japan.
Eur J Pharmacol. 2007 Jun 22;565(1-3):166-70. doi: 10.1016/j.ejphar.2007.03.025. Epub 2007 Mar 24.
Cardiac effects of L/N-type Ca2+ channel blocker cilnidipine were assessed using the halothane-anesthetized canine model. Cilnidipine (1 and 3 microg/kg, i.v.) lowered the mean blood pressure by -5 and -14 mm Hg, respectively, without affecting the heart rate or maximum upstroke velocity of left ventricular pressure. Isoproterenol or acetylcholine was intravenously injected to directly or indirectly induce the positive chronotropic responses, respectively. Cilnidipine hardly affected the isoproterenol-induced cardiac responses, but it attenuated the acetylcholine-induced reflex tachycardia to 63-78% of the pre-drug control level. These results suggest that clinically relevant doses of cilnidipine can directly attenuate the sympathetic tone.
使用氟烷麻醉的犬模型评估了L/N型钙通道阻滞剂西尼地平对心脏的作用。西尼地平（静脉注射，剂量为1和3微克/千克）分别使平均血压降低了5毫米汞柱和14毫米汞柱，而不影响心率或左心室压力的最大上升速度。分别静脉注射异丙肾上腺素或乙酰胆碱以直接或间接诱导正性变时反应。西尼地平几乎不影响异丙肾上腺素诱导的心脏反应，但它将乙酰胆碱诱导的反射性心动过速减弱至给药前对照水平的63%-78%。这些结果表明，临床相关剂量的西尼地平可直接减弱交感神经张力。
