1. The present study was designed to examine the effects of intracerebroventricular (ICV) injection of different α and $\beta$ adrenergic receptor antagonists on leptin-induced hypophagia in broiler chickens.

2. The study consisted of six experiments. In all experiments, chickens were deprived of feed for 3 h prior to the ICV injections and thereafter were returned immediately to the individual cages and cumulative feed intake, based on the percentage of body weight, was measured at 30, 60 and 120 min post-injection.

3. In experiment 1, leptin (2.5, 5 or 10 µg) were injected in birds. In experiment 2, groups received either control solution, prazosin (10 nmol), leptin (10 µg) or a co-injection of prazosin (10 nmol) and leptin (10 µg). The other experiments were conducted as experiment 2, but instead of prazosine (10 nmol), yohimbine (13 nmol) was used in experiment 3, metoprolol (24 nmol) in experiment 4, ICI 118,551 (5 nmol) in experiment 5 and SR 59230R (5 nmol) in experiment 6 were injected either in a group or in combination with leptin (10 µg).

4. The results of this study revealed a dose-dependent hypophagic effect of leptin and, in experiment 5, ICV co-injection of ICI118, 551 (5 nmol) and leptin (10 µg) significantly attenuated this effect (P˂0.5). These results suggest that the hypophagic effect of leptin is probably mediated by β2 adrenergic receptors in chickens.

1.本研究旨在检查脑室内注射不同α和α的脑室（ICV）的作用。 $\beta$ 肾上腺素能受体拮抗剂对肉鸡瘦素引起的吞噬的影响。

2.研究包括六个实验。在所有实验中，在注射ICV之前，将鸡禁食3小时，然后立即将鸡放回各个笼子中，并根据体重百分比在出雏后30、60和120分钟测量累积的采食量。注射。

3.在实验1中，将瘦蛋白（2.5、5或10 µg）注射到禽类中。在实验2中，各组接受对照组溶液，哌唑嗪（10 nmol），瘦素（10 µg）或共注射哌唑嗪（10 nmol）和瘦素（10 µg）。其他实验均作为实验2进行，但在实验3中使用育亨宾（13 nmol）代替了哌唑嗪（10 nmol），在实验4中使用美托洛尔（24 nmol），在实验5中使用ICI 118,551（5 nmol），并且使用SR 59230R实验6中的5摩尔（5 nmol）或与瘦素（10μg）一起注射。

4.这项研究的结果显示出瘦素的剂量依赖性下吞咽作用，在实验5中，ICV共同注射ICI118、551（5 nmol）和瘦素（10 µg）显着减弱了这种作用（P˂0.5）。这些结果表明，瘦素的低吞噬作用可能是由鸡的β2肾上腺素能受体介导的。