Effect of shenmai injection on L-type calcium channel of diaphragmatic muscle cells in rats.
- Author:
Li-min ZHAO
1
;
Sheng-dao XIONG
;
Ru-ji NIU
Author Information
- Publication Type:Journal Article
- MeSH: Animals; Calcium Channels, L-Type; metabolism; Diaphragm; metabolism; Drug Combinations; Drugs, Chinese Herbal; Female; Male; Muscle Contraction; drug effects; Muscle Fibers, Skeletal; metabolism; Patch-Clamp Techniques; Plant Extracts; pharmacology; Rats; Rats, Wistar
- From: Chinese Journal of Integrated Traditional and Western Medicine 2003;23(8):599-602
- CountryChina
- Language:Chinese
-
Abstract:
OBJECTIVETo explore the effect of Shenmai Injection (SMI) on L-type calcium channel of diaphragmatic muscle cells in rats.
METHODSSingle diaphragmatic muscle cell of rats was obtained by the acute enzyme isolation method and the standard whole-cell patch clamp technique was used to record the inward peak L-type calcium current (IPLC) and current-voltage relationship curve of diaphragmatic muscle cells of 7 rats, and to compare the effects of SMI in various concentrations on them.
RESULTSWhen keeping the electric potential at -80 mV, stimulation frequency 0.5 Hz, clamp time 300 ms, stepped voltage 10 mV, and depolarized to +60 mV, 10 microliters/ml of SMI could only cause the mean IPLC of rat's diaphragmatic muscle cells increased from -6.9 +/- 0.6 pA/pF to -7.5 +/- 0.7 pA/pF, the amplification being (9.2 +/- 2.8)%, comparison between those of pre-treatment and post-treatment showed insignificant difference. But when the concentration of SMI increased to 50 microliters/ml and 100 microliters/ml, the mean IPLC increased to -8.4 +/- 0.6 pA/pF and -9.2 +/- 0.6 pA/pF, respectively, and the amplification was (22.4 +/- 1.7)% and (34.6 +/- 4.6)% respectively, showing significant difference to that of pre-treatment (P < 0.05). However, SMI showed no significant effect on maximal activation potential and reversal potential.
CONCLUSIONSMI can activate the calcium channel of diaphragmatic muscle cells in rats, increase the influx of Ca2+, so as to strengthen the contraction of diaphragmatic muscle, which may be one of the ionic channel mechanisms of SMI in treating diaphragmatic muscle fatigue in clinical practice.