OBJECTIVETo investigate the role of tumor suppressor PTEN in cardiac hypertrophy, the expression of PTEN mRNA and protein was analyzed in the tissue of left ventricle in abdominal aorta constricted-induced cardiac hypertrophic rats which treated with and without captopril. The expression of PTEN mRNA and protein in cultured neonatal rat cardiomyocyte treated with AngII was studied.

METHODSSD rats were divided into control group, hypertrophy group and captopril group. The expression of PTEN in different groups at 2 and 4 weeks after operation as well as in cultured neonatal rat cardiomyocyte treated with AngII was detected by RT-PCR and Western blot. The localization of PTEN in left ventricle and cultured cardiomyocyte was determined by immunohistochemistry.

RESULTS(1) Compared with control group, the expressions of PTEN mRNA and protein in left ventricle of hypertrophy group as well as in cultured cardiomyocyte treated with AngII were reduced. (2) Compared with hypertrophy group, the expressions of PTEN mRNA and protein in left ventricle of captopril group were upregulated, which were similar to those of control group. (3) Positive immunohistochemical staining of PTEN was located in the nucleus of cardiomyocytes.

CONCLUSIONPTEN may play a negative regulation role in the process of cardiac hypertrophy, and the role of PTEN may be closely related with renin-angiotensin system.