TY - JOUR
T1 - The anorexic effect of alpha-melanocyte-stimulating hormone is mediated by corticotrophin-releasing factor in chicks
AU - Tachibana, Tetsuya
AU - Oikawa, Daichi
AU - Takahashi, Hirokazu
AU - Boswell, Tim
AU - Furuse, Mitsuhiro
N1 - Funding Information:
The authors are grateful to Momoka Sato, Kyushu University, Japan, for her assistance. This work was supported by Grant-in-Aid for Young Scientists (No. 15780187), Grant-in-Aid for Scientific Research from Japan Society for the Promotion of Science (No. 16380191 and 17208023) and the Inamori Foundation.
PY - 2007/5
Y1 - 2007/5
N2 - Alpha-melanocyte-stimulating hormone (alpha-MSH) is recognized as an anorexic peptide in the brain of vertebrates, but its mechanism of action has not been identified in birds. Therefore, we investigated whether the anorexic effect of alpha-MSH is mediated by corticotrophin-releasing factor (CRF) in the domestic chick. Firstly, we found that intracerebroventricular (ICV) injection of alpha-MSH dose dependently increased plasma corticosterone (CORT) concentration. This effect was partly attenuated by co-injection of astressin, a CRF receptor antagonist, demonstrating that alpha-MSH stimulated CORT secretion by activating CRF neurons. The alpha-MSH-elicited CORT release was not attenuated by the injection of agouti-related protein, an endogenous melanocortin-4 (MC4) receptor antagonist, suggesting that alpha-MSH stimulated CRF neurons through MC4 receptor-independent pathways. Finally, we found that the anorexic effect of alpha-MSH was partly attenuated by astressin. The present results suggest that the anorexic effect of alpha-MSH in the chick brain is mediated in part by activation of CRF neurons.
AB - Alpha-melanocyte-stimulating hormone (alpha-MSH) is recognized as an anorexic peptide in the brain of vertebrates, but its mechanism of action has not been identified in birds. Therefore, we investigated whether the anorexic effect of alpha-MSH is mediated by corticotrophin-releasing factor (CRF) in the domestic chick. Firstly, we found that intracerebroventricular (ICV) injection of alpha-MSH dose dependently increased plasma corticosterone (CORT) concentration. This effect was partly attenuated by co-injection of astressin, a CRF receptor antagonist, demonstrating that alpha-MSH stimulated CORT secretion by activating CRF neurons. The alpha-MSH-elicited CORT release was not attenuated by the injection of agouti-related protein, an endogenous melanocortin-4 (MC4) receptor antagonist, suggesting that alpha-MSH stimulated CRF neurons through MC4 receptor-independent pathways. Finally, we found that the anorexic effect of alpha-MSH was partly attenuated by astressin. The present results suggest that the anorexic effect of alpha-MSH in the chick brain is mediated in part by activation of CRF neurons.
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U2 - 10.1016/j.cbpa.2006.12.044
DO - 10.1016/j.cbpa.2006.12.044
M3 - Article
C2 - 17321768
AN - SCOPUS:33947504225
SN - 1095-6433
VL - 147
SP - 173
EP - 178
JO - Comparative Biochemistry and Physiology - A Molecular and Integrative Physiology
JF - Comparative Biochemistry and Physiology - A Molecular and Integrative Physiology
IS - 1
ER -