The role of orexin-1 receptors in physiologic responses evoked by microinjection of PgE2 or muscimol into the medial preoptic area

NEUROSCIENCE LETTERS

卷:498

Article

Rusyniak, Daniel E.^1,2  Zaretsky, Dmitry V.¹  Zaretskaia, Maria V.¹  DiMicco, Joseph A.² 

[1] Indiana Univ Sch Med, Dept Emergency Med, Indianapolis, IN 46202 USA

[2] Indiana Univ Sch Med, Dept Pharmacol & Toxicol, Indianapolis, IN 46202 USA

关键词: Microinjection;    Orexin;    Muscimol;    Prostaglandin E2;    Hypothalamus;   

DOI  :  10.1016/j.neulet.2011.05.006

来源: Elsevier

【 摘 要 】

The medial preoptic area (mPOA) of the hypothalamus has long been thought to play an important role in both fever production and thermoregulation. Microinjections of prostaglandin E2 (PgE2) or the GABA(A) agonist muscimol into the mPOA cause similar increases in body temperature, heart rate, and blood pressure. Microinjections of these compounds however evoke different behavioral responses with muscimol increasing and PgE2 having no effect on locomotion. The purpose of this study was to determine the role of orexin-1 receptors in mediating these dissimilar responses. Systemic injections of the orexin-1 receptor antagonist SB-334867 reduced temperature and cardiovascular responses produced by microinjections of muscimol, but had no effect on either response produced by PgE2. SB-334867 did not significantly decrease locomotion evoked by microinjections of muscimol into the mPOA. These data suggest that there are two central nervous system circuits involved in increasing body temperature, heart rate and blood pressure: one circuit activated by muscimol, involving orexin neurons, and a separate orexin-independent circuit activated by PgE2. (C) 2011 Elsevier Ireland Ltd. All rights reserved.

【 授权许可】

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