Effect of exhaustive exercise preconditioning on GAP-43 and Nogo-A in rats with cerebral ischemia reperfusion

Objective To observe the effect of exhaustive exercise preconditioning on GAP-43 and Nogo-A in rats with cerebral ischemia reperfusion. Methods 90 rats were randomly divided into sham operation group, group of cerebral ischemia reperfusion(I/R) and exhaustive exercise preconditioning group.Rats were sacrificed at 6 h, 1 d, 3 d and 7 d respectively after injury. Neural functions were detected by shuttle box.Morphological changes of hippocampal neural cells were observed by HE staining. Expressions of GAP-43 and Nogo-A were detected respectively by immunohistochemistry and RT-PCR technology. Results Compared with the sham group, the death rate of apoptotic neurons in I/R group was decreased(6 h: (30.97±2.09)%, 1 d: (38.41±1.10)%, 3 d: (46.81±2.04)%, 1 d: (43.46±1.57)%), the index of learning and memory ability(AARR-7 d: (38.00±12.60)%, PAL-7 d: (27.90±1.79)s) and expression of GAP-43 were decreased(6 h: (2.89±0.85), 1 d: (4.06±0.25), 3 d: (4.78±0.98), 7 d: (7.02±0.21)), the expression of Nogo-A was increased(6 h: (2.93±0.19), 1 d: (5.47±0.32), 3 d: (4.62±0.26), 7 d: (4.12±1.11))(P<0.05). Compared with I/R group, the death rate of apoptotic neurons in exhaustive exercise preconditioning group were decreased, the index of learning and memory ability(AARR-7 d: (20.66±7.60)%, PAL-7 d: (35.53±2.41)s) and expression of GAP-43 were decreased(6 h: (2.03±0.14), 1 d: (2.92±0.27), 3 d: (3.35±0.34), 7 d: (5.24±0.52)), the expression of Nogo-A were increased(6 h: (3.92±0.51), 1 d: (6.90±0.79), 3 d: (5.87±0.48), 7 d: (5.37±0.50))(P<0.05). Conclusion Exhaustive exercise preconditioning aggravates the injury of neurons and neural function, which is related to the regulation of GAP-43 and Nogo-A in the hippocampus of rats. Key words: Exhaustive exercise; Cerebral ischemia reperfusion; GAP-43; Nogo-A