胰高血糖素对禁食和再喂养大鼠脂肪酸合成的体内作用。

In vivo effects of glucagon on fatty acid synthesis in fasted and refed rats.

作者信息

Klain G J

出版信息

J Nutr. 1977 Jun;107(6):942-8. doi: 10.1093/jn/107.6.942.

DOI:10.1093/jn/107.6.942

Abstract

Since altered nutritional states evoke compensatory changes in systemic levels of several hormones, the present study was conducted to determine in vivo effects of glucagon and insulin on hepatic and adipose tissue lipogenesis in fed, fasted (3-days) and refed (3-days) rats. Compared to the fed controls, glucagon reduced hepatic fatty acid synthesis and acetyl CoA carboxylase activity by 62% and 65% in fed rats, and by 51% and 48%, respectively, in refed rats. In contrast, glucagon had no effect on fatty acid synthesis or acetyl CoA carboxylase activity in adipose tissue of any of the three experimental groups. Exogenous insulin antagonized the glucagon effects and restored hepatic fatty acid synthesis and enzyme activity in fed or refed rats. No glucagon or insulin effects were observed in fasting rats. In addition, glucagon reduced in vivo incorporation of acetate into hepatic cholesterol by about 33% and into fatty acids of the liver, and heart and the kidney by 33%, 77% and 30%, respectively. The hormone had no effect on fatty acid synthesis in the muscle.

摘要

由于营养状态的改变会引起多种激素全身水平的代偿性变化，因此进行本研究以确定胰高血糖素和胰岛素对进食、禁食（3天）和再进食（3天）大鼠肝脏和脂肪组织脂肪生成的体内影响。与进食对照组相比，胰高血糖素使进食大鼠的肝脏脂肪酸合成和乙酰辅酶A羧化酶活性分别降低62%和65%，使再进食大鼠的上述指标分别降低51%和48%。相反，胰高血糖素对三个实验组中任何一组的脂肪组织脂肪酸合成或乙酰辅酶A羧化酶活性均无影响。外源性胰岛素拮抗胰高血糖素的作用，并恢复进食或再进食大鼠的肝脏脂肪酸合成及酶活性。在禁食大鼠中未观察到胰高血糖素或胰岛素的作用。此外，胰高血糖素使体内乙酸掺入肝脏胆固醇的量减少约33%，使乙酸掺入肝脏、心脏和肾脏脂肪酸的量分别减少33%、77%和30%。该激素对肌肉中的脂肪酸合成没有影响。