PTEN negatively regulates isoproterenol-induced cardiac hypertrophy and effects of captopril on PTEN expression
Zhou, Y-zhong.; Zhu, S-jun.; Yu, L-jun.; Tian, Y.; Wang, J.
Zhonghua Xin Xue Guan Bing Za Zhi 33(8): 738-742
2005
ISSN/ISBN: 0253-3758 PMID: 16188065 Document Number: 590350
Objective To examine the negative regulation role of PTEN in isoproterenol-induced cardiac hypertrophy by testing the expression of PTEN mRNA and protein and to explore the effects of captopril ( Cap) on PTEN expression. Methods Twenty four rats were randomly divided into three groups: control group, ISO group, and ISO + Cap group. The following parameters were examined: body weight (BW), heart weight (HW), left ventricular weight (LVW), left ventricular end-diastolic pressure (LVEDP), left ventricular end-systolic pressure ( LVESP) and +/- dp/dt(max). The ratio of HW/BW and LVW/BW was calculated. PTEN mRNA and protein were tested by RT-PCR and Western blot, respectively. Results (1) Compared with the control group, the ratio of HW/BW and LVW/BW, LVEDP and LVESP were all increased in ISO group and ISO + Cap group (P<0.05), but +/- dp/dt(max) was decreased (P<0.05); (2) compared with the ISO group,the ratio of HW/BW and LVW/BW, LVEDP, LVESP were all decreased in ISO + Cap group (P<0.05), but +/- dp/dt(max) was increased (P<0.05); (3) compared with the control group, PTEN mRNA and protein were up-regulated in ISO group and ISO + Cap group; (4) compared with the ISO group, PTEN mRNA and protein were up-regulated in ISO + Cap group. Conclusions PTEN mRNA and protein are up-regulated in isoproterenol-induced cardiac hypertrophy. Captopril can up-regulate PTEN expression in cardiac hypertrophy. There is a negative regulative mechanism in cardiac hypertrophy process, in which PTEN is probably an endogenous negative regulator of cardiac hypertrophy.