Abnormal coronary function in mice deficient in alpha1H T-type Ca2+ channels |
| |
Authors: | Chen Chien-Chang Lamping Kathryn G Nuno Daniel W Barresi Rita Prouty Sally J Lavoie Julie L Cribbs Leanne L England Sarah K Sigmund Curt D Weiss Robert M Williamson Roger A Hill Joseph A Campbell Kevin P |
| |
Institution: | Howard Hughes Medical Institute, University of Iowa, Iowa City, IA 52242, USA. |
| |
Abstract: | Calcium ion (Ca2+) influx through voltage-gated Ca2+ channels is important for the regulation of vascular tone. Activation of L-type Ca2+ channels initiates muscle contraction; however, the role of T-type Ca2+ channels (T-channels) is not clear. We show that mice deficient in the alpha1H T-type Ca2+ channel (alpha(1)3.2-null) have constitutively constricted coronary arterioles and focal myocardial fibrosis. Coronary arteries isolated from alpha(1)3.2-null arteries showed normal contractile responses, but reduced relaxation in response to acetylcholine and nitroprusside. Furthermore, acute blockade of T-channels with Ni2+ prevented relaxation of wild-type coronary arteries. Thus, Ca2+ influx through alpha1H T-type Ca2+ channels is essential for normal relaxation of coronary arteries. |
| |
Keywords: | |
本文献已被 PubMed 等数据库收录! |
|