YAO Yan, HUANG Congª²Xin, CHEN Gao

    Department of Cardiology, People¬ðs Hospital, Wuhan University, Wuhan 430060, China

    ¡¾Abstract¡¿ AIM: To investigate the expressions of mRNA of ICaª²L and ICaª²T across the canine left ventricular wall and to explore the possible molecular mechanism and significance of electrical heterogeneity. METHODS: The mRNA expressions of the ICaª²L ¦Áª²subunit Cav1.2, ICaª²T transcript Cav3.1 were quantified by semiquantitative RTª²PCR in tissue sections obtained from different regions of canine left ventricle including epicardium (Ep), midª²myocardium (M) and endocardium (En). RESULTS: The mRNA of Cav1.2 was expressed much more strongly in M and in En than that in Ep (P<0.05), but there was no significant difference between M and En (P>0.05). Cav3.1 mRNA was almost absent in Ep, while just a little in M and En. CONCLUSION: There are considerable variations of calcium channels across the canie left ventricular wall,which may be the molecular basis of the distribution of ICaª²L and ICaª²T, and may play an important part in the occurence and drug treatment of reentry arrhythmias. ......