[Angiotensin II induced cardiac hypertrophy is blocked by PTEN via suppressing Ca2+/Calcineurin pathway].

Objective: To investigate the effects of PTEN on Ang II induced cardiomyocyte hypertrophy and subsequent Ca(2+)/Calcineurin pathway changes.

Methods: Primary cultured neonatal rat cardiomyocytes were cultured and were treated with phosphate-buffered saline, empty adenovirus (Ad-GFP), or adenovirus encoding for PTEN (Ad-PTEN-GFP) for 48 h and Ang II (10(-7) mol/L) was added to the medium for another 24 h. Cells were harvested and intracellular Ca(2+) concentration ([Ca(2+)] i) was determined by Fura-2/AM ratio imaging analysis; PTEN, ANF, beta-MHC and CaNAbeta mRNA evaluated with RT-PCR; PTEN and CaNAbeta protein by Western blot; CaN phosphatase activity by CaN detecting kits.

Results: PTEN at mRNA and protein levels were significantly higher in Ad-PTEN-GFP treated cardiomyocytes than that of Ad-GFP treated cardiomyocytes. Ang II stimulation upregulated [Ca(2+)] i, CaNAbeta at mRNA and protein levels and CaN phosphatase activity in Ad-GFP treated cardiomyocytes but not in Ad-PTEN-GFP treated cardiomyocytes.

Conclusions: Cardiac hypertrophy induced by Ang II could be blocked by PTEN overexpression via suppressing Ca(2+)/Calcineurin pathway.