The Effects Of Monocrotaline On Right Ventricular Function And The Expression Of Cardiac TRPC6in Rats

Objective: To discuss the function effects on right ventricles of rats in monocrotaline(MCT) induced cardiac hypertrophy within3weeks, and the expression andpathophysiological significance of transient receptor potential normative (TRPC)6onright ventricular hypertrophy in Rats.Methods: The SD rats were randomly divided into control group (CON), andMonocrotaline administration (MCT group). CON group, treated with normal saline.MCT group, a dose of60mg/kg MCT was given to SD rats by single intraperitonealinjection. In two models,We measured:①Right ventricular systolic pressure (RVSP),right ventricular pressure maximum rate of rise (RV+dp/dtmax), right ventricularpressure maximum rate of descent (RV－dp/dtmax)；②Right ventricular mass index(RVMI);③right ventricular myocardium tissue sections were stained by HE andobserved under light microscope;④Real-time polymerase chain reaction (Real-time-PCR) and were performed to detect the expression of TRPC6.⑤Western blot wereperformed to detect the expression of TRPC6protein according to the RT-PCR results.Results: In comparison of the CON group:①RVSP and RVMI were markedly elevated(P<0.01)in MCT group;②RV+dp/dtmaxwere markedly elevated (P<0.01), RV-dp/dtmaxwere markedly decreased (P <0.01) in MCT group;③Right ventricular myocardialfibers become thick, intracellular myofibrils increase in the number of disorderedarrangement of the myocardial fibers, the nuclei deeply stained, the shape of the nucleiis not regularity in MCT groups;④The levels of mRNA in MCT group were markedlyelevated than in CON group (P<0.05)；⑤The levels of protein of TRPC6in MCT groupwere markedly elevated than in CON group (P<0.05).Conclusion:3weeks injected MCT could induce:①SD rats suffered right ventricularhypertrophy.②Raised the expression of mRNA and protein of TRPC6channel in rightventricular, TRPC6may be involved in the development of cardiac hypertrophy.