Corp E S, Melville L D, Greenberg D, Gibbs J, Smith G P
Department of Psychiatry, Cornell University Medical College, New York 10021.
Am J Physiol. 1990 Aug;259(2 Pt 2):R317-23. doi: 10.1152/ajpregu.1990.259.2.R317.
We studied the effect of fourth intracerebroventricular administration of neuropeptide Y (NPY) and peptide YY (PYY) on ingestive and other behaviors in awake nondeprived rats. Injection of NPY or PYY into the fourth ventricle produced a significant dose-related increase in food intake and reduction in the latency to eat. PYY was more potent than NPY in increasing food intake and decreasing latency to eat, suggesting that PYY-preferring receptors sensitive to the orexigenic effects of NPY and PYY exist in the hindbrain. In addition, both peptides increased water intake when food was present but not when food was absent, suggesting that a neural substrate supporting a direct action of NPY and PYY on water intake is not present in the hindbrain. In time sampling of behaviors occurring during a 90-min feeding test, we found that both peptides increased the time spent eating and reduced grooming. In addition PYY, but not NPY, reduced apparent sleep and increased exploratory activity. This suggests that PYY, but not NPY, influences a hindbrain neural substrate involved in sleep and activity.
我们研究了向清醒未禁食大鼠的第四脑室注射神经肽Y（NPY）和肽YY（PYY）对摄食及其他行为的影响。向第四脑室注射NPY或PYY会使食物摄入量显著增加且进食潜伏期缩短，呈剂量依赖性。PYY在增加食物摄入量和缩短进食潜伏期方面比NPY更有效，这表明在后脑中存在对NPY和PYY的促食欲作用敏感的PYY偏好性受体。此外，当有食物时两种肽都会增加水的摄入量，但无食物时则不会，这表明后脑中不存在支持NPY和PYY对水摄入量直接作用的神经基质。在90分钟进食测试期间对行为进行定时采样时，我们发现两种肽都会增加进食时间并减少梳理行为。此外，PYY而非NPY会减少明显的睡眠时间并增加探索活动。这表明PYY而非NPY会影响参与睡眠和活动的后脑神经基质。
