Suzuki K, Imada T, Gao F, Ma H, Nagata T
Kyowa Bio-Research Laboratories, Co., Ltd., Ube, Japan.
Arzneimittelforschung. 1994 Feb;44(2):129-33.
Microradioautographic study of [3H]-benidipine hydrochloride (KW-3049, CAS 91599-74-5) and nitrendipine (CAS 39562-70-4) localization was performed in the supramesenteric arteries of the spontaneously hypertensive rats (SHR) at 10 and 30 min after intravenous administration or in vitro incubation. The distribution of silver grains was observed by light and electron microscopy and the number of grains was counted in the tunicae intima, media and adventitia of the arteries. Areas of the correlated part of the artery were measured and the grain count per area was calculated. The grain count of [3H]-benidipine hydrochloride showed almost uniform distribution in the tunicae intima and media, which was compared at 10 and 30 min after the administration both in the in vivo and in the in vitro studies. The grain density of [3H]-nitrendipine to the tunicae intima and media increased time-dependently. Electron microscopic observation revealed that the fine distribution of [3H]-benidipine hydrochloride was mainly localized on the plasma membrane and on the cytoplasm of the cellular components of the mesenteric artery. The result suggested that the distribution of [3H]-benidipine hydrochloride was related to its pharmacologically active site, i.e. plasma membrane of the tunica intima and the smooth muscle cells of the tunica media.
对[3H]-盐酸贝尼地平（KW-3049，CAS 91599-74-5）和尼群地平（CAS 39562-70-4）的定位进行了微放射自显影研究，研究对象为自发性高血压大鼠（SHR）的肠系膜上动脉，给药时间为静脉注射后10分钟和30分钟，或体外孵育后。通过光学显微镜和电子显微镜观察银颗粒的分布，并对动脉内膜、中膜和外膜中的颗粒数量进行计数。测量动脉相关部位的面积，并计算每单位面积的颗粒计数。[3H]-盐酸贝尼地平的颗粒计数在体内和体外研究中，给药后10分钟和30分钟时，在内膜和中膜中均显示出几乎均匀的分布。[3H]-尼群地平在内膜和中膜的颗粒密度呈时间依赖性增加。电子显微镜观察显示，[3H]-盐酸贝尼地平的精细分布主要定位于肠系膜动脉细胞成分的质膜和细胞质上。结果表明，[3H]-盐酸贝尼地平的分布与其药理活性部位有关，即内膜的质膜和中膜的平滑肌细胞。
