title: Effect of shenmai injection on L-type calcium current of diaphragmatic muscle in rats.
abstract: In this study, whole cell patch clamp recording technique was employed to investigate the effect of Shenmai Injection (SMI) on L-type calcium current of diaphragmatic muscle in rats. The result showed that when the diaphragmatic muscle cell was held at -80 mV and depolarized to +60 mV, 10 microl/ml, 50 microl/ml and 100 microl/ml SMI enhanced the inner peak L-type calcium current from -(6.8 +/- 0.7) pA/pF (n=7) to -(7.3 +/- 0.8) pA/pF (P>0.05, n=7), -(8.6 +/- 1.0) pA/pF (P<0.05, n=7) and -(9.4 +/- 1.2) pA/pF (P<0.05, n=7), respectively, The rates of L-type calcium current were increased by (7.34 +/- 2.37)%, (25.72 +/- 5.94)%, and (38.16 +/- 7.33)%, respectively. However, it had no significant effect on maximal activation potential and reversal potential. Our results suggested that SMI could activate the calcium channel of the diaphragmatic fibers of the rats, increase the influx of Ca2+, and enhance the contractility of diaphragmatic muscles.
authors.affiliation: Department of Respiratory Diseases, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China.
authors.forename: Limin
authors.initials: L
authors.lastname: Zhao
authors.forename: Shengdao
authors.initials: S
authors.lastname: Xiong
authors.forename: Ruji
authors.initials: R
authors.lastname: Niu
authors.forename: Yongjian
authors.initials: Y
authors.lastname: Xu
authors.forename: Zhengxiang
authors.initials: Z
authors.lastname: Zhang
mesh_terms: D000818:Animals; D002118:Calcium / Q000378:metabolism; D020746:Calcium Channels, L-Type / Q000187:drug effects*; D003964:Diaphragm / Q000187:drug effects / Q000378:metabolism*; D004338:Drug Combinations; D004365:Drugs, Chinese Herbal; D008297:Male; D018408:Patch-Clamp Techniques; D010936:Plant Extracts / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar
chemical_list: D020746:Calcium Channels, L-Type; D004338:Drug Combinations; D004365:Drugs, Chinese Herbal; D010936:Plant Extracts; C009252:fructus schizandrae, radix ginseng, radix ophiopogonis drug combination; D002118:Calcium