Abstract: To investigate the effect of capsaicin or irbesartan on the phenotypic transformation of spontaneously hypertensive rats vascular smooth muscle cells (VSMCs).After construction of spontaneously hypertensive rats vascular smooth muscle cells in vitro and identification by immunofluorescence,cells were treated with capsaicin (20 μmol/L,10 μmol/L,5 μmol/L) or irbesartanc (1 μmol/L) directly or specifically inhibiting the expression of CD36,the changes of α-SMA,OPN mRNA and protein expression levels were detected by qRT-PCR and Western Blot,and CD36 was detected by flow cytometry.Compared with the control group,OPN and CD36 expression were down-regulated in the capsaicin group and irbesartan group,α-SMA expression was up-regulated.After inhibiting the expression of CD36,in the capsaicin group or irbesartan group OPN expression was down-regulated,α-SMA expression was up-regulated.Compared with the pre-blocking groups,in the irbesartan group capsaicin groups of post-blocking,OPN expressions were down-regulated,α-SMA expressions were up-regulated.The results showed that capsaicin or irbesartan could up-regulate α-SMA expression,down-regulate OPN expression,inhibit the expression of CD36 to promote VSMCs in spontaneously hypertensive rats transform from synthetic phenotype to contractile phenotype,thus promoting restoration of normal physiological function for the arterial wall,reducing blood pressure in spontaneously hypertensive rats.

Key words: capsaicin, irbesartan, spontaneous hypertension, vascular smooth muscle cells, phenotypic transformation