The Role Of Serum And Glucocorticoid Induced Protein Kinase-1 On Stimulating Rat Vascular Smooth Muscle Cells Proliferation And Molecular Mechanism

Objective To investigate the role and potential mechanisms of serum and glucocorticoid induced kinase-1(SGK₁)in rat vascular smooth muscle cells(VSMCS)proliferation under hypertensive renal injury.Methods VSMCs were primarily cultured by explant method from the renal artery of male SD rats. VSMCs were cultured and transfected with pIRES2-EGFP-S422D SGK₁ mutant(SD), plasmid containing SGK₁ mutant or blank plasmid. Non-transfected VSMCs were used as control group. Then the VSMCs were divided into 3 groups transfected with SD, transfected with FP, non-transfected NT. The effect of SGK₁ on the proliferation of VSMCs was investigated by cell counting and MTT assay. RT-PCR was used to examine the SGK₁ mRNA expression. Analyzed the cell-cycle using flow cytometry. Westeren Blot used to detected the expression of p21^cip1, p27^kip1 , P-GSK₃ and PCNA.Results The proliferation of VSMCs infected with SGK₁ was excited. The number of cells that arrested in G0/G1 phase were decreased. The expression of PCNA and P-GSK₃ were upregulated after the VSMCs transfection with SGK₁ and the expression of p21^cip1and p27^kip1 was downregulated.Conclusions SGK₁ may stimulates VSMCs proliferation and therefore may play an active part in hypertensive renal injury.