Orexin-A (hypocretin-1) is possibly involved in generation of anxiety-like behavior

Author: Suzuki, M.; Beuckmann, C.T.; Shikata, K.; Ogura, H.; Sawai, T.

Description: Orexins (hypocretins) are neuropeptides expressed specifically in neurons in the lateral hypothalamic area and are known to be involved in the regulation of vigilance and feeding behavior. However, the relationship between orexin and emotional behaviors like anxiety is still poorly understood. Therefore, in this report we evaluated the effect of intracerebroventricular injection of orexin-A in two major anxiety tests, the light-dark exploration test (mouse) and the elevated plus-maze test (mouse, rat). Orexin increased time spent in the dark compartment in the light-dark test and time spent on the closed arms in the elevated plus-maze test. These results were not caused by a hypothetical sedative or activity-inducing effect of orexin-A because spontaneous locomotor activity did not alter upon orexin-A application under novel conditions. We therefore suggest an anxiogenic effect of orexin-A. To our knowledge, this is the first report about a relationship between orexin-A and anxiety.

Subject headings: Analysis of Variance; Animals; Anxiety/etiology/physiopathology; Behavior, Animal/drug effects; Disease Models, Animal; Dose-Response Relationship, Drug; Exploratory Behavior/drug effects; Injections, Intraventricular/methods; Intracellular Signaling Peptides and Proteins/toxicity; Male; Maze Learning/drug effects; Mice; Mice, Inbred C57BL; Motor Activity/drug effects; Neuropeptides/toxicity; Orexins; Rats; Rats, Wistar; Time Factors

Keywords: Orexin-A (hypocretin-1) is possibly involved in generation of anxiety-like behavior

Publication year: 2005

Journal or book title: Brain Research

Volume: 1044

Issue: 1

Pages: 116-121

Find the full text : https://www.sciencedirect.com/science/article/pii/S0006899305003720

Find more like this one (cited by): https://scholar.google.com/scholar?cites=11872354225840444640&as_sdt=1000005&sciodt=0,16&hl=en

Type: Journal Article

Serial number: 2889