Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
2023218 | Regulatory Peptides | 2008 | 5 Pages |
Abstract
The feeding-relevant pathway by which food restriction (FR) augments cocaine action is unknown. Systemic administration of the 28-amino acid acylated peptide ghrelin (1-10Â nmol) increases food intake in rats and circulating levels of rat ghrelin are up-regulated by FR. The present experiment examined the impact of repeated administration of ghrelin or vehicle on the subsequent capacity of cocaine to enhance locomotion in rats. Male Sprague-Dawley rats were pretreated daily for seven days with 0, 5 or 10Â nmol rat ghrelin (i.p.) in the home cage. On the 8th day, rats were transported to a testing room, placed in a locomotion chamber for 15Â min, and then injected (i.p.) with 0, 7.5, or 15Â mg/kg cocaine hydrochloride. Locomotor activity was monitored over a 45Â min post-cocaine period. Pretreatment with 5 or 10Â nmol ghrelin alone did not significantly increase basal locomotion relative to that of the 0Â nmol ghrelin group. Rats pretreated with 5Â nmol or 10Â nmol ghrelin showed an enhanced locomotor response after treatment with 15Â mg/kg cocaine relative to rats treated with 0Â nmol ghrelin. These results indicate that acute injection of ghrelin, at a feeding-relevant dose, can augment the acute effects of cocaine on locomotion in rats.
Related Topics
Life Sciences
Biochemistry, Genetics and Molecular Biology
Biochemistry
Authors
Paul J. Wellman, Chelsie N. Hollas, Audrea E. Elliott,