{"title":"Identification of calcium-channel receptors in intact animals.","authors":"W R Roeske, H R Lee, H I Yamamura, H Schoemaker","doi":"","DOIUrl":null,"url":null,"abstract":"<p><p>In this study, we demonstrate the in vivo labeling by [3H]nitrendipine ([3H]NTD) of peripheral tissues and the brain in Sprague-Dawley rats. Specific binding is decreased in a dose-dependent manner by nifedipine, with a mean inhibitory dose of 2-10 mg/kg (i.p.). Thin-layer chromatography of the particulate-bound radioactivity reveals that the predominant tritiated drug bound in the left ventricle and the cerebral cortex is [3H]NTD, whereas metabolites constitute the main species in the liver. Peak radioactivity is seen at 15 min following an intravenous injection of [3H]NTD. Highly perfused tissues such as the heart, brain, and lung have significant [3H]NTD binding. In contrast to previously reported in vitro studies, [3H]NTD binding is low in the aorta, skeletal muscle, and ileum. This in vivo animal model is suitable for pharmacokinetic and physiological studies of the calcium channel in intact animals.</p>","PeriodicalId":77831,"journal":{"name":"Advances in myocardiology","volume":null,"pages":null},"PeriodicalIF":0.0000,"publicationDate":"1985-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Advances in myocardiology","FirstCategoryId":"1085","ListUrlMain":"","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 0
Abstract
In this study, we demonstrate the in vivo labeling by [3H]nitrendipine ([3H]NTD) of peripheral tissues and the brain in Sprague-Dawley rats. Specific binding is decreased in a dose-dependent manner by nifedipine, with a mean inhibitory dose of 2-10 mg/kg (i.p.). Thin-layer chromatography of the particulate-bound radioactivity reveals that the predominant tritiated drug bound in the left ventricle and the cerebral cortex is [3H]NTD, whereas metabolites constitute the main species in the liver. Peak radioactivity is seen at 15 min following an intravenous injection of [3H]NTD. Highly perfused tissues such as the heart, brain, and lung have significant [3H]NTD binding. In contrast to previously reported in vitro studies, [3H]NTD binding is low in the aorta, skeletal muscle, and ileum. This in vivo animal model is suitable for pharmacokinetic and physiological studies of the calcium channel in intact animals.