19：第十八章 动物的采食量(1学时)

二、调节采食量的其他途径

（3）leptin：瘦蛋白，或瘦素

肥胖基因的表达产物。 具有激素作用，调节体内脂肪的储存量。 胰岛素刺激其分泌，β3 -肾上腺素兴奋剂降低脂肪组织 中Leptin基因的表达。

限制采食时Leptin立即下降，以防止体重下降；

过量采食（特别是慢性过食）时，Leptin浓度提高。

Ghrelin and leptin, their sites of origin and way of action on hypothalamic centers to affect food intake and BMI. The

inhibitory influence of Hp infection on the release of ghrelin and stimulatory action on leptin release are also marked.

a. A lipostat regulates weight across time

b.

Hypothalam ic

neuropeptid es involved in long term regulation 1) NPY and Orexins stimulate feeding 2) Melanocorti ns and CRH inhibit feeding