In the present study, the effects of angiotension II on the expression of protooncogene c-fos and c-myc in the left ventricle were investigated on Langedorff heart preparations. It was observed that angiotensin induced both c-fos and c-myc expression in a dose-dependent manner and the c-fos expression showed an earlier appearance than c-myc. All these induced expressions were blocked by a Angiotensin II receptor antagonist saralasin. The Angiotensin II induced expression of c-fos was also blocked by TTX, but the c-myc gene expression was unaffected.