Whitcomb D C, Puccio A M, Vigna S R, Taylor I L, Hoffman G E
Department of Medicine, University of Pittsburgh, PA 15261, USA. whitcomb+@pitt.edu
Brain Res. 1997 Jun 20;760(1-2):137-49. doi: 10.1016/s0006-8993(97)00295-3.
Pancreatic polypeptide (PP) is a regulatory peptide that modulates gastrointestinal function. Previously we demonstrated PP receptors in the brainstem and interpeduncular nucleus, and the PP receptors in the brainstem appear to modulate gastric motility and pancreatic exocrine secretion. The purpose of this study is to extend our understanding of the distribution of PP receptors in the rat brain in order to determine the systems that are potentially modulated by PP. Rat brains were studied using 125I-PP receptor autoradiography on cryostat sections of the entire brain cut in three planes (horizontal, sagittal, and coronal). Brain regions exhibiting PP binding sites were confirmed when identified in all three planes of section. Saturable PP binding was identified in the hypothalamus (arcuate and paraventricular n), the rostral forebrain (medial preoptic area, anterior olfactory nucleus, islands of Calleja, the dorsal endopiriform n, piriform cortex, and the bed n of the stria terminalis), medial amygdaloid n; the thalamus (anteromedial thal. n; reuniens thal. n; and paraventricular thal n), the interpeduncular red nucleus, substantia nigra, parabrachial n; locus coeruleus, mesencephalic trigeminal n, dorsal motor n of the vagus, the n solitary tract, and the area postrema. We conclude that PP receptors are distributed widely throughout the rat brain. The distribution of many of these PP binding sites corresponds to brain regions regulating digestion and autonomic function. We speculate, based on the patterns of binding in the olfactory and limbic systems, that PP receptors might be involved in positive reinforcement of ingestion behavioral as well as modulation of gastrointestinal function.
胰多肽（PP）是一种调节肽，可调节胃肠功能。此前我们在脑干和脚间核中证实了PP受体，脑干中的PP受体似乎可调节胃动力和胰腺外分泌。本研究的目的是扩展我们对大鼠脑中PP受体分布的认识，以确定可能受PP调节的系统。使用125I-PP受体放射自显影技术对大鼠脑在三个平面（水平、矢状和冠状）上切成的低温恒温器切片进行研究。当在所有三个切片平面中均能识别出显示PP结合位点的脑区时，予以确认。在下丘脑（弓状核和室旁核）、前脑嘴侧（内侧视前区、前嗅核、Calleja岛、背内侧梨状核、梨状皮质和终纹床核）、内侧杏仁核；丘脑（丘脑前内侧核、丘脑连合核和丘脑室旁核）、脚间红核、黑质、臂旁核；蓝斑、中脑三叉神经核、迷走神经背运动核、孤束核和最后区中发现了可饱和的PP结合。我们得出结论，PP受体广泛分布于大鼠脑中。许多这些PP结合位点的分布与调节消化和自主功能的脑区相对应。基于嗅觉和边缘系统中的结合模式，我们推测PP受体可能参与摄食行为的正强化以及胃肠功能的调节。
