| The purpose of the present study is to investigate the effect of aerobic exercise on the energy balance in rats. A diabetic rat model which is hyperglycosemia and hypoinsulinemia is produced . This article illuminates some neuro-endocrine mechanisms on the diabetic rats and the probably ways that sports can improve the abnormity of energy metabolism in diabetic rats by observing the variety and the relationship of the regulatory peptides which is closely relative with pathologic alteration of glycometabolism and lipometabolism on blood and brain.The adult male Wistar rats (195 ?lOg body wt) were adopted in this experiment. The rats were randomly divided into the following groups: 1.normal control group; 2.normal exercise group; 3.diabetic non-exercise group; 4.diabetic exercise group. The food and water intaken and body weights of the animals pre and post experiment were recorded. The rats were trained with swimming in exercise groups ,60min/day and 6 days/wk for 6 wk.Diabetes was induced by streptozotocin (STZ) (55 mg/kg body wt by intraperitoned injection) which was dissolved in citric acid-phosphate buffer PH4.4 and verified 24 hours later by the presence of hyperglycemia and hyperglycosuria. Three days later diabetic rats presented hyperphagia, hyperposia and hyperuresis. Control groups received citric acid-phosphate buffer of isodose.This study measured serum insulin, blood glucose, blood leptin, plasma NPY and the concentration of hypothalamus protein, insulin, NPY, GAL, CCK, BN. The expression of NPY gene in paraventricular nucleus (PVN) and arcuate nucleus(ARC) were determined by nonisotopic in situ hybridization. The level of TNF-a of the two non-exercise groups in serum and hypothalamus was measured too.The results suggested as follows: Long-term aerobic exercise could increase plasma leptin, which restrained the expression of NPY gene in hypothalamus and regulated the transcription of NPY, and so that the synthesis of NPY decreased whereas body produced more heat and consumed more energy. In addition, CCK in hypothalamus raised after long-term aerobic training. It might be an important mechanism for lowering appetite, decreasing splanchnic adipopexis and reducing body weight, which were induced by long-term aerobic exercise. After diabetic rat model was conducted by STZ, they showed special symptomsof diabete: hyperphagia, hyperposia, hyperuresis and loss of body weight, and at the same time they displayed hyperglycosemia and hypoinsulinemia. This proved that glycometabolism was disorder because STZ induced rats insulopathic and that the diabetic animal model of hyperglycosemia and hypoinsulinemia was successfully produced. The diabetic rats showed that serum leptin clearly decreased, the gene expression and the protein concentration of NPY in ARC obviously increased, CCK evidently reduced and GAL raised. It was demonstrated that there is a possible correlation between excessive appetite of STZ-induced diabetic rats and the increasing of NPY transcription as well as protein translation in hypothalamus, the excessive appetite which might be the result of appetite-regulatory factor acting synthetically. Diabetic rats showed excessive appetite and hyperphagia, but they still became emaciated and lost body weight. This because NPY acted on sympathetic nerve obstructively and insulin was absolutely or relatively inadequate, which affected glycometabolism, lipometabolism and proteometabolism seriouly, and a lot of water was egested from urine on account of hyperglycosuria and osmosis-diuresis. It was demonstrated that long-term aerobic exercise could abate excessive appetite, decrease the food intaken, and increase splanchnic lipopexia and body weight due to the action of appetite-regulatory peptide. This may further explain that long-term aerobic exercise could contribute to the increasing of insulinogenesis and insulin sensitivity, to the absorption and utilization of carbohydrate, and to the improvement of glycometabolism disorder and energy metabolism abnormality, which...
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