Research for the regulation of voluntary exercise and energy metabolism by appetite-regulating factors

我们建立了一种新的动物模型，称为运动(自发跑步德岛-四国)大鼠，它表现出高自愿车轮跑和低水平的血浆总生长激素水平。本研究的目的是利用运动动物模型，研究由Ghrelin前体产生的食欲调节因子--Ghrelin和OBest atin对小鼠自主跑轮和能量代谢的影响。我们将运动大鼠分为两组，分别肌肉注射生理盐水、Ghrelin或Ghrelin+奥斯汀6天(100。G/kg体重/天)。Ghrelin组的自主车轮运行显著减少。Ghrelin组的食物摄入量、体重和腹部内脏脂肪显著增加。奥斯汀抑制了Ghrelin诱导的食物摄入量、体重和腹部内脏脂肪增加，但对自愿车轮运行没有任何影响。我们的结果提示，Ghrelin和OBest atin可能对自愿运动或食欲产生不同的作用途径。一些食欲调节因子可能会调节自愿运动或能量代谢。

We established a new animal model called SPORTS(Spontaneously-Running Tokushima-Shikoku) rats, which show high voluntary wheel running and low level of plasma total Ghrelin. The aim of this study was to investigate the in vivo effect of Ghrelin and Obestatin, which are appetite-regulating factors generated from prepro-Ghrelin, on voluntary wheel running and energy metabolism using the SPORTS animal model. We divided SPORTS rats into two groups, which were intramuscularly administrated Saline, Ghrelin, or Ghrelin+ Obestatin for six days(100. g/ kg BW/ day). Voluntary wheel running was significantly decreased in Ghrelin groups. Food intake, body weight, and abdominal visceral fat were significantly increased in Ghrelin groups. Obestatin suppressed Ghrelin-induced food intake, body weight, and abdominal visceral fat gains, but did not have any effect on voluntary wheel running. Our results suggest that Ghrelin and Obestatin may exert different pathway on the voluntary exercise or appetite. Some appetite-regulating factors may regulate voluntary exercise or energy metabolism.