Effect Of Swimming In Cold Water On Function And Structure Of Peripheral Nerve In Diabetic Rats

Objective: The incidence rate of diabetes peripheral neuropathy disease is extremely high, which seriously affects patient's quality of life, because there is no effective treatment, it is also in the medical difficult problem. It is currently thought that swimming (water temperature 35℃) can not only prevent the occurrence of diabetic neuropathy, but also play a therapeutic role for diabetic peripheral neuropathy. With respect to low or warm temperature water, cold water (temperature below 26℃) is roughly the same to the indoor temperature, so it can be acquired conveniently and economically. But there is few studies of effect of swimming in cold water (temperature below 26℃or less) on peripheral neuropathy in diabetic rats. This study explores the sea and fresh water placed in the room with relatively constant water temperature (water temperature 20℃), and observes the effect on function and structure of peripheral nerve of diabetic rats swimming in cold water, and compares the effects of seawater and freshwater. It is in the hope of providing a experimental basis for the prevention and treatment of diabetic peripheral neuropathy.Methods: 48 healthy male SD rats weighing in the 250±20g were randomly selected 10 as the normal control group A, 30 successful diabetes rat models were made and randomly divided into diabetic model (B) group, seawater swimming (C), fresh water swimming (D) group, with 10 rats in each group. Rats in group C and group D group were swimming groups, rats in group C were placed in a bucket in the seawater, rats in group D were placed in the bucket of tap water, the depths of water in each group were both 50cm. The rats were treated with warming for 20 minutes until they had swum to fatigue. The training was carried on continuously five times a week with two days of rest for eight weeks. At the end of the fourth and eighth week of training experiment, fasting blood glucose of rats, body weight and caudal nerve conduction velocity (CNCV) were measured. The nerve structures of tails were observed at the end of eighth weeks.Results: Rats of group A were in good state of mind, shiny coat and normal eating, drinking as well as defecation. Rats of group B had the gradual emergence of polydipsia, polyphagia, polyuria, hair loss, brash and other symptoms. Rats in group C and group D had polydipsia, polyuria, polyphagia, but significantly less than those in group B. At the fourth week, compared with group A , fasting blood glucose in group B increased, weight decreased, CNCV slowed, there were significant difference between groups (P < 0.05), in group C and group D, the fasting blood glucose increased, the weight decreased, there were significant difference between groups (P < 0.05), CNCV did not change significantly (P > 0.05). Compared with group B and group C, fasting blood glucose in group D was lower, the weight gained, CNCV increased rapidly, there was significant difference between groups (P < 0.05). There was no significant difference in fasting blood glucose, weight and CNCV between group C and group D (P > 0.05). At the eighth week, compared with group A , fasting blood glucose increased, weight decreased and CNCV slowed down in group B, there was significant deference between groups (P < 0.05), fasting blood glucose of group C and group D increased, weight decreased, CNCV slowed down, there was significant change between groups (P < 0.05). Compared with group B and group C, fasting blood glucose of group D was lower, weight increased, CNCV added rapidly, there was significant change between groups (P < 0.05). There was no significant difference between fasting blood glucose, weight and CNCV in group C and group D (P > 0.05). And the end of the eighth weeks caudal nerve were observed in the electron microscope, changes in myelin sheath of nerve fibers under the light microscope. Under the light microscope tightly packed myelinated nerve fibers with full and complete myelin could be seen in group A. There were nerve fibers gap expansions, myelin swelling, different thickness of myelin sheath, loose structure, and lamellar structure disorder, accompanied by vacuolar degeneration. Nerve fibers gap expansion, myelin integrity; local fluffy, mild demyelination could be seen in group B, group C and group D. Under electron microscopy group A nerve fiber axis is complete, clear. nerve fiber and mitochondr in axoplasmic inside. The whole myelin form has changed. group C and group D part of nerve fibers is mild myelinated. Its swelling parts appear different degree of distortion, shrinks.Conclusion: Diabetic rats swimming in cold water can reduce fasting blood glucose and weight loss, prevent the occurrence of diabetic neuropathy and delay the development of diabetic peripheral neuropathy. However, no significant difference was detected in fasting blood glucose, body weight and peripheral neuropathy between seawater group and fresh water group in this experiment.