破坏大鼠极后区对胆囊收缩素抑制摄食跑速作用的影响

THE EFFECTS OF AREA POSTREMA LESION ON RUNNING SPEED FOR FOOD IN THE RAT

胆囊收缩素(CCK)能抑制大鼠的摄食量和摄食跑速。本文向腹腔内注入CCK(10μg/kg)后15分钟内发现大鼠的摄食量和在迷宫内的摄食跑速都明显降低。破坏大鼠的极后区后,向腹腔内注入等量的CCK,则CCK抑制摄食作用明显减弱,开始的15分钟内摄食量显著增多,摄食跑速明显加快。提示大鼠的极后区在CCK引起的摄食抑制作用中起重要作用,极后区可能是CCK在脑干内的一个重要的感受器。在破坏了极后区同时又破坏了孤束核的动物,亦有降低CCK抑制摄食的作用。但与正常大鼠对照组比较,破坏极后区的大鼠摄食量减少,而摄食跑速没有明显差别。

Area postrema(AP) is a receptor area of CCK which is known to reduce food intake. Does it affect the motivation for running speed to food? Sprague-Dawley male rats were trained at high speeds (up to 50 cm/sec) in a 1 meter runway for food. They received 10 μg/kg CCK in 1 ml saline i, p. or 1ml 0.9% saline i.p. and their food intake and running speed were measured at 0, 15, 30 and 60 min. Before AP lesion, i.p. CCK rats' food intake(within 30 min)is less than that after. i.p. saline(p<0.05)and the running speed is much slower than that after i.p, saline(p<0.001). After the AP lesions (with 1 week recovery)the running speed is not significantly different between the CCK and the vehicle treatment. The data demonstrate that CCK inhibits food intake and the motivatign for food via its action On the AP.