ABSTRACT
Objective To explore whether the cAMP-PKA-pCREB signal pathway plays a role in promoting the recovery of motor function after rehabilitation training in cerebral ischemia-reperfusion rats .Methods The middle cerebral artery occlusion model ( MCAO) was established by modified Longa nylon occlusion method in adult male Sprague -Dawley rats.The 84 MCAO rats were selected and randomly assigned to four groups:the natural recovery group without any special training (group B, n=24),natural recovery group with Rp-cAMP (group C, n=24), rehabilitation training group (group D, n=18) and rehabilitation training with Rp-cAMP (group E, n=18), and in addition a control group (group A, n =12).To establish rat MCAO models immediately after injection of Rp-cAMP into the lateral ventricle of the brain .The rats in the groups D and E were trained by balance beam , bar rotating and rolling exercises started at 48 h after MCAO.The ex-pression of PKA was determined by enzyme-linked immunosorbent assay ( ELISA) and the pCREB protein expression was detected by Western blot assay .Motor function was assessed by balance beam test .Results (1) The motor function score in the group C was significantly higher than that of group B , suggesting that Rp-cAMP inhibited the recovery of motor func-tion in the cerebral ischemia-reperfusion rats .The score of group D was significantly lower than that of groups B and E , in-dicating that Rp-cAMP inhibited the promoting effect of rehabilitation training on motor function in the cerebral ischemia -reperfusion rats.(2) The expressions of PKA and pCREB proteins detected at 2nd, 7th, 14th, and 21th days after surgery showed that their expressions in the group D were significantly higher than those of the groups B and E , indicating that re-habilitation training promoted the expression of PKA and pCREB , and Rp-cAMP significantly inhibited the promoting effect of rehabilitation training on the expressions of PKA and pCREB proteins .Conclusion cAMP/PKA-pCREB signal trans-duction pathway may mediate a promoting effect of rehabilitation training on the recovery of motor function after ischemic stroke in rats.