Abstract: AIM:To explore the varied expression level of connective tissue growth factor(CTGF) in rat vascular smooth muscle cells(VSMCs) and its significance.METHODS:Using age-matched Wistar-Kyoto(WKY) rats as control,the lumen diameter(L),media thickness(M),and media/lumen ratio(M/L) from 4-week-old and 16-week-old SHR were detected,respectively.Protein expression in vascular cells of WKY rats and SHR was then detected by immunohistochemical techniques and Western blot,and mRNA level was analyzed by real-time reverse transcription-polymerase chain reaction with SYBR(RT-qPCR).RESULTS:The ratio of L,M and M/L in 4-week-old SHR were similar to that in 4-week-old WKY rats(P>0.05),and the protein and mRNA level of Col III in vascular cells of 4-week-old SHR were also similar to that of age-matched rats WKY rats.CTGF expression was upregulated significantly(P<0.05).In 16-week-old SHR,the ratio of M/L were lower compared with age-matched WKY rats(P<0.01).Protein and mRNA levels of Col III and CTGF in 16-week-old SHR were significantly higher than that of 16-week-old WKY(P<0.01).CONCLUSION:Abnormal hemodynamic changes may regulate CTGF expression in VSMCs.Increased expression of CTGF may contribute to vascular remodeling in hypertension.