Abstract:

Objective To observe the effect of nicorandil，an ATP⁃sensitive potassium channel opener，on the expression of SYP and GAP43 in adult rats with cerebral ischemia⁃reperfusion，and to explore the mechanism of nicorandil in synaptic plasticity. Methods Rats were divided into Sham + Vehicle group（n = 34），MCAO + Vehicle group（n = 34）and MCAO + Nicorandil group（n = 34）according to the randomization principle. Middle cerebral artery occlusion（MCAO）model procedure was used by the intraluminal suture model. Nissl staining was used to assess the infarct volume，and modified neurological severity scores（mNSS）were calculated to assess the neurological function on the 1st，3rd，7th and 14th days after surgery. Morris Water Maze test was used to detect the learning and memory function. PCR and Western blot were used to detect the mRNA and protein levels of SYP and GAP43. Results Compared with those in MCAO + Vehicle group，the infarct volume of MCAO + Nicorandil group was significantly reduced；neurological impairment was significantly ameliorated；learning and memory disorders were improved；and the mRNA and protein levels of SYP and GAP43 were increased. The differences were statistically significant（P < 0.05）. Conclusion The treatment with Nicorandil can promote functional recovery of neurological deficits in MCAO rats. The possible mechanism is closely related to the up⁃regulation of expression of SYP and GAP43，thus to improve synaptic plasticity.

Key words: