Abstract:Aim To investigate the effects of exercise training on the function of the CaL channels in cerebral arterial smooth muscle cells of aging spontaneously hypertensive rats. Methods 18 3-month-old male Wistar-Kyoto (WKY) rats and 18 spontaneously hypertensive rats (SHR) were used, besides, 16-month-old male WKY and SHR were randomly assigned into either a sedentary group or an exercise-trained group, each group contained 18 rats. The rats in exercise-trained groups ran on a motor treadmill (60 min/d, 5 d/w) at 16~18 m/min for 8 weeks. After 8 weeks training, body weight and heart weight among these groups were measured. The CaL channel function and the expression of CaL channel α1C protein in cerebral artery were measured by whole-cell patch-clamp technique and Western blot. Results(1)Aging effects:Both heart rate and systolic blood pressure in SHR were much higher than those of the same age WKY rats, the systolic blood pressure in 16-month-old rats were significantly higher than the same strain in 3-month-old rats; The CaL channel current density and CaL channel α1C protein expression in young SHR were extremely increased compared with WKY, whereas aging markedly decreased CaL channel current density and CaL channel α1C protein expression in both hypertensive and normotensive rats with no significant differences between them. (2) Exercise effects:The heart weight index (heart weight/ body weight) in aging exercise-trained groups were markedly higher than those in sedentary strains; Exercise training greatly lowered the systolic blood pressure, and increased CaL channel current density and CaL channel α1C protein expression in SHR. Conclusion Aging reduced CaL channel function of cerebral artery from SHR, while exercise training attenuated remodeling of CaL channel.