AIM:To investigate the changes of short-chain acyl-CoA dehydrogenase(SCAD)in hypertensive vascular remodeling and to explore the relationship between SCAD and vascular remodeling in hypertension.METHODS:The spontaneously hypertensive rats(SHR;24 weeks old)and Wistar rats(24 weeks old)were used as experimental con-trol groups.The SHR and Wistar rats of 16 weeks old were trained by swimming as experimental groups.The systolic pres-sure was measured periodically.The thickness of vascular wall and the diameter of the vascular lumen were measured.The contents of ROS and ATP,the enzyme activity of SCAD, and the expression of SCAD at mRNA and protein levels in the aorta were determined.The free fatty acid in the serum and aorta was also measured.RESULTS:Compared with Wistar group,the diameter of vascular lumen decreased in SHR group.The thickness of vascular wall,the ratio of vascular wall and the diameter of vascular lumen,and the blood pressure in SHR group were increased significantly(P<0.05).Com-pared with SHR group,the diameter of vascular lumen increased in SHR +swim group.The thickness of vascular wall,the ratio of vascular wall and the diameter of vascular lumen,and the blood pressure in SHR +swim group were decreased sig-nificantly.Compared with control group, the expression of SCAD at mRNA and protein levels, the enzyme activity of SCAD,and the content of ATP were decreased in SHR group.However,the free fatty acid in the serum and aorta,and the content of ROS in the aorta were increased in SHR group.The expression of SCAD at mRNA and protein levels,the en-zyme activity of SCAD,the content of ATP were increased in Wistar +swim group and SHR +swim group.However, the free fatty acid in serum and aorta,and the content of ROS in the aorta were decreased in Wistar +swim group and SHR+swim group.CONCLUSION: Decrease in SCAD expression may be associated with hypertensive vascular remodeling. Swimming training can reverse hypertensive vascular remodeling by increasing the expression of SCAD in the aorta.