Currie P J, Coscina D V
Department of Psychology, 71 W. Warren Ave., Wayne State University, Detroit, MI 48202, USA.
Brain Res. 1998 Aug 24;803(1-2):212-7. doi: 10.1016/s0006-8993(98)00643-x.
The objective of the present report was to characterize further the potential interactive effects of NPY and 5-HT on feeding and whole-body calorimetry. Specifically, several experiments examined the impact of various 5-HT receptor agonists on NPY stimulated eating and alterations in respiratory quotient (RQ). This included the 5-HT1A/1B receptor agonist RU 24969, the 5-HT1B/2C agonist TFMPP and the 5-HT2A/2C agonist DOI. In feeding tests conducted at the onset of the dark cycle, RU 24969, TFMPP and DOI were administered 5 min prior to PVN injection of NPY and food intake was measured 1 h postinjection. The metabolic effects of NPY following similar pretreatment were monitored using an open-circuit calorimeter measuring the volume of oxygen consumed (VO2), carbon dioxide produced (VCO2) and RQ (VCO2/VO2). PVN injection of NPY (50-100 pmol) potentiated feeding and evoked reliable increases in RQ. DOI (5-20 nmol), but not RU 24969 (5-20 nmol) or TFMPP (10-40 nmol), antagonized NPY induced eating and blocked the peptide's effects on RQ. These findings suggest that 5-HT2A receptors within the PVN modulate NPY's effect on feeding and energy substrate utilization at the start of the nocturnal period.
本报告的目的是进一步描述神经肽Y（NPY）和5-羟色胺（5-HT）对进食及全身热量测定的潜在交互作用。具体而言，多项实验研究了不同5-HT受体激动剂对NPY刺激进食及呼吸商（RQ）变化的影响。这包括5-HT1A/1B受体激动剂RU 24969、5-HT1B/2C激动剂三氟甲基苯哌嗪（TFMPP）和5-HT2A/2C激动剂DOI。在黑暗周期开始时进行的进食测试中，在向室旁核（PVN）注射NPY前5分钟给予RU 24969、TFMPP和DOI，并在注射后1小时测量食物摄入量。使用开路热量计监测类似预处理后NPY的代谢效应，该热量计可测量消耗氧气量（VO2）、产生二氧化碳量（VCO2）和RQ（VCO2/VO2）。向PVN注射NPY（50 - 100皮摩尔）可增强进食并引起RQ可靠升高。DOI（5 - 20纳摩尔）可拮抗NPY诱导的进食并阻断该肽对RQ的影响，但RU 24969（5 - 20纳摩尔）或TFMPP（10 - 40纳摩尔）则无此作用。这些发现表明，PVN内的5-HT2A受体在夜间开始时调节NPY对进食和能量底物利用的作用。
