Leibowitz S F, Sladek C, Spencer L, Tempel D
Rockefeller University, New York, NY 10021.
Brain Res Bull. 1988 Dec;21(6):905-12. doi: 10.1016/0361-9230(88)90025-1.
The paraventricular nucleus (PVN) is known to have an important function in mediating a variety of behavioral and endocrine responses. In the present study, the responsiveness of the PVN to the effects of the coexisting neurotransmitters, neuropeptide Y (NPY), epinephrine (EPI) and norepinephrine (NE), was examined. Albino rats were each chronically implanted with a swivel brain-cannula that permits chemicals to be infused without disturbing the animals' ongoing behavior. When infused into the PVN, each of these neurotransmitters elicited a reliable feeding response during the first hour after injection. The response to EPI was significantly stronger than that of NE and NPY, while the latency to eat after injection was considerably longer for NPY as compared to the catecholamines. In tests with food absent, each of these substances also increased blood levels of corticosterone (EPI greater than NE = NPY) and vasopressin (NPY greater than EPI greater than NE) and revealed a significant positive correlation between circulating levels of these two hormones. In addition, EPI and NE, in contrast to NPY, caused a simultaneous rise in blood glucose, producing levels that were positively correlated with the hormones. No relationship, however, was detected between these endocrine changes and the rats' feeding-stimulatory responses. Together with other evidence, these results suggest that adrenergic as well as noradrenergic innervation to the PVN has a key role in the behavioral and endocrine systems of this nucleus and, moreover, that NPY generally mimics the effects of these catecholamines in the PVN.
已知室旁核（PVN）在介导多种行为和内分泌反应中具有重要作用。在本研究中，检测了PVN对共存神经递质神经肽Y（NPY）、肾上腺素（EPI）和去甲肾上腺素（NE）作用的反应性。给白化大鼠每只长期植入一个可旋转脑套管，该套管允许在不干扰动物正在进行的行为的情况下注入化学物质。当注入PVN时，这些神经递质中的每一种在注射后的第一小时内都会引发可靠的进食反应。对EPI的反应明显强于NE和NPY，而与儿茶酚胺相比，注射后NPY的进食潜伏期长得多。在无食物的试验中，这些物质中的每一种还会增加皮质酮（EPI大于NE = NPY）和血管加压素（NPY大于EPI大于NE）的血液水平，并显示这两种激素的循环水平之间存在显著正相关。此外，与NPY不同，EPI和NE会导致血糖同时升高，产生与激素呈正相关的水平。然而，未检测到这些内分泌变化与大鼠进食刺激反应之间的关系。与其他证据一起，这些结果表明，PVN的肾上腺素能和去甲肾上腺素能神经支配在该核的行为和内分泌系统中起关键作用，而且，NPY在PVN中通常模仿这些儿茶酚胺的作用。
