The Influence On Rats' Learning Memory Capability And The Hippocampal Expressing Of NGF And N-NOS Under Different Training Load

Different training load can affect learning and memory; at the same time also affect the changes of the hippocampal neutral cell. Nerve Growth Factor (NGF) can highly concentrated in the central nervous system, it have these functions: enhance the activity of the neurotransmitters, promote the synthesis of metabolism, maintain the nerve cell differentiation, growth, development,and promote damaged cell repair, it is closely related to the spatial memory formation, maintenance and closely related to the development of the intellect about learning and memory. Nitric oxide synthase is an important enzyme to catalytic and synthesis NO, NO has a dual role, physiological doses of NO is essential on the activities of the nervous system, but excessive levels of NO will have a nervous system toxicity. In this paper, a different load of swimming training is the stressor, while have a behavioral study on rats, take the changes in the learning and memory as the breakthrough point, through hippocampus NGF and n-NOS expression, discuss the rats'learning memory neurobiological and its mechanisms of different training load.Randomly divide into the control group C, the small intensity group S, the moderate intensity group M, the high intensity group H for 8 weeks swimming training without weight-bearing in this experiment .And the day after the end of the experiment, all of the rats have the Y-maze test, through the rats'response behaviors to test the rats'ability of spatial learning and memory changes. Use the immune chemical method to measure the content of the nerve growth factor (NGF) and neuronal-nitric oxide synthase (n-NOS), according to the different expression of the hippocampus neutral after sports, discuss the effects of rats'learning and memory and the expression of the hippocampus function under the different loads of training.This experiment demonstrate that rats learn to reach the standard requiring the number of training group H and group M compared with group C have a significant difference (P﹤0.05); group H compared with group M have a very significant difference (P﹤0.01); group S compared with group C have no statistically significant (p>0.05). Rats appear the errors number in the response of the target process group H and group M compared with group C have a significant difference (P﹤0.05); group H compared with group M have a very significant difference (P﹤0.01); group S compared with group C have no statistically significant (p>0.05). Rats appear the errors number in the response of the memory process group H and group M compared with group C have a significant difference (P﹤0.05); group H compared with group M have a very significant difference (P﹤0.01); group S compared with group C have no statistically significant (p>0.05). The expression of NGF in group H compared with group C have a very significant difference (P﹤0.01); group M compared with group C have a significant difference (P﹤0.05); group H compared with group M have a very significant difference (P﹤0.01); group S compared with group C have no statistically significant (p>0.05). The expression of n-NOS in group H compared with group C have a very significant difference (P﹤0.01); group M compared with group C have a very significant difference (P﹤0.01); group H compared with group M have a very significant difference (P﹤0.01); group S compared with group C have a significant difference (P﹤0.05).This experiment shows that 8 weeks moderate load swimming training on rats'learning and memory have a certain promotion, 8 weeks high-load swimming training on rats'learning and memory have a certain obstruction. Movement can lead to increase the expression of NGF in hippocampal neurons, and with the training load increasing the expression of NGF is also increased. The expression of NGF in a certain range can promote rats'learning and memory capabilities; but the expression of NGF more than a certain range, have an impediment on the improvement of learning and memory. 8 weeks moderate load swimming training on rats'learning and memory have a certain promotion, 8 weeks high-load swimming training on rats'learning and memory have a certain obstruction. Movement can bring about the increasing expression of n-NOS, and with the training load increasing the expression of n-NOS is also increased. The expression of n-NOS in a certain range can promote rats'learning and memory capabilities; but the expression of NGF more than a certain range, have an impediment on the improvement of learning and memory.