文章基本信息

标题：EFFECTS OF CALCIUM BLOCKERS AND Mn2+ ON THE RESPONSE OF ISOLATED RAT IRIS SPHINCTER AND DILATOR MUSCLES TO AGONISTS AND Ca2+
本地全文：下载
作者：SATOSHI NARITA ; MINORU WATANABE
期刊名称：Biological and Pharmaceutical Bulletin
印刷版ISSN：0918-6158
电子版ISSN：1347-5215
出版年度：1982
卷号：5
期号：4
页码：285-294
DOI：10.1248/bpb1978.5.285
出版社：The Pharmaceutical Society of Japan
摘要：Effects of calcium blockers and Mn on the mechanical response of the isolated rat iris sphincter and the dilator were investigated. The contraction of the sphincter in response to acetylcholine, the contraction of the dilator in response to norepinephrine and the relaxation-contraction of the dilator in response to acetylcholine and also resting tone of dilator muscle were strongly dependent to external Ca concentration to different extents, while these responses and the tone were scarcely affected by calcium blockers, D-600, diltiazem (all 1μM), or nitroprusside Na (0.1mM). In depolarized sphincter muscle (in the presence of atropine and phentolamine), the contraction induced by externally added Ca was reduced moderately by the Ca-blockers but this effect was far weaker than that expected from their effect on other smooth muscles. Mn (0.3 mM) moderately reduced the calcium contraction of depolarized sphincter. In depolarized dilator muscle, the contraction induced by Ca was not inhibited effectively by any of these Ca blockers but was moderately reduced by Mn. It is suggested that the rat iris muscles are resistant to "organic Ca-blockers" but sensitive to Mn, an "inorganic Ca-blocker".
关键词：diltiazem