Abstract
It has been well documented that matrine, a tetracyclo-quinolizindine alkaloid, possessed a positive inotropic effect. However, the underlying mechanisms at the cellular and ion channel levels have not been completely clarified. Therefore, the present study was designed to identify the cellular target and the mechanisms of inotropic effect of matrine. Guinea pig papillary muscles were used to study the contractile force of the heart and ventricular myocytes were used to study L-type calcium channel (ICa-L) and intracellular calcium concentration ([Ca2+]i). In electrically driven papillary muscles, matrine enhanced the contractile force in a dose-dependent manner and the positive inotropic effect was not inhibited by alpha- and beta-adrenergic receptor antagonists. In ventricular myocytes, matrine also increased ICa-L in a dose-dependent manner and shifted the inactivation curve toward right. Matrine markedly enhanced the KCl-induced elevations of [Ca2+]i. In a conclusion, ICa-L might be a main target of matrine. Matrine enhanced [Ca2+]i by stimulating ICa-L and exerted positive inotropic effects on electrically driven guinea pig papillary muscles.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
