Zhou B J, Li Y S, Fu S X
Department of Pharmacology, Hebei Medical College, Shijiazhuang, China.
Zhongguo Yao Li Xue Bao. 1994 Jul;15(4):327-30.
m-Nisoldipine caused a concentration-dependent depression of the contractile response and 45Ca influx evoked by KCl in isolated rat thoracic aorta. The IC50 value for contraction and 45Ca influx were 0.69 (95% confidence limits 0.32-1.5) nmol.L-1 and 0.35 (95% confidence limits 0.06-2.0) nmol.L-1, respectively. There was a positive correlation between the inhibition of KCl-evoked contraction and 45Ca influx (r = 0.996). m-Nisoldipine (0.1-10 mumol.L-1) did not influence the 45Ca influx into resting cells and failed to inhibit noradrenaline (1.0 mumol.L-1)-evoked contraction and 45Ca influx. The results suggest that the relaxant effect of m-nisoldipine on rat aorta may be closely related to the blockade of Ca2+ entry through a potential-dependent calcium channel.
间尼索地平可使氯化钾诱发的离体大鼠胸主动脉收缩反应和45Ca内流呈浓度依赖性降低。收缩反应和45Ca内流的IC50值分别为0.69（95%置信限0.32 - 1.5）nmol·L-1和0.35（95%置信限0.06 - 2.0）nmol·L-1。氯化钾诱发的收缩抑制与45Ca内流之间存在正相关（r = 0.996）。间尼索地平（0.1 - 10 μmol·L-1）不影响静息细胞的45Ca内流，也不能抑制去甲肾上腺素（1.0 μmol·L-1）诱发的收缩和45Ca内流。结果表明，间尼索地平对大鼠主动脉的舒张作用可能与通过电压依赖性钙通道阻断Ca2+内流密切相关。
