OBJECTIVE: To apply rapamycin to target mTOR and discuss its effect on the proliferation of rat heart valve interstitial cells.
Methods: The rat valve interstitial cells were isolated in vitro and then cultivated and verified; the cells were randomly divided into two groups: rapamycin group and control group; MTT method was used to detect and draw the growth curve of rat valve interstitial cells before and after drug administration; The effect of rapamycin on cell cycle was detected by cytometer; the mRNA expression of S6 and P70S6K in cells was detected by RT-PCR; the protein expression of S6, P70S6K, P-S6 and P-P70S6K in cells was detected by Western blotting.
RESULTS: The rat valve interstitial cells obtained in vitro were successfully cultured separately; the cell activity in the control group was significantly higher than that in the drug-added group (P<0.05), and the growth of the cells in the drug-added group was slowed down. Flow cytometry showed that there was no significant difference in the proportion of cells in each cycle between the drug-added group and the control group; the phosphorylation of S6 protein and P70S6K protein in the drug-added group cells decreased (P<0.05).
Conclusion: The reason why rapamycin can inhibit the proliferation of valve interstitial cells may not be caused by changing the cell cycle but by inhibiting mTOR and down-regulating the phosphorylation of its target proteins S6 and P70S6K.