| Literature DB >> 24981835 |
Beth Lute1, William Jou1, Dalya M Lateef2, Margalit Goldgof2, Cuiying Xiao2, Ramón A Piñol2, Alexxai V Kravitz2, Nicole R Miller3, Yuning George Huang4, Clemence Girardet5, Andrew A Butler5, Oksana Gavrilova1, Marc L Reitman6.
Abstract
The melanocortin system regulates metabolic homeostasis and inflammation. Melanocortin agonists have contradictorily been reported to both increase and decrease metabolic rate and body temperature. We find two distinct physiologic responses occurring at similar doses. Intraperitoneal administration of the nonselective melanocortin agonist MTII causes a melanocortin-4 receptor (Mc4r)-mediated hypermetabolism/hyperthermia. This is preceded by a profound, transient hypometabolism/hypothermia that is preserved in mice lacking any one of Mc1r, Mc3r, Mc4r, or Mc5r. Three other melanocortin agonists also caused hypothermia, which is actively achieved via seeking a cool environment, vasodilation, and inhibition of brown adipose tissue thermogenesis. These results suggest that the hypometabolic/hypothermic effect of MTII is not due to a failure of thermoregulation. The hypometabolism/hypothermia was prevented by dopamine antagonists, and MTII selectively activated arcuate nucleus dopaminergic neurons, suggesting that these neurons may contribute to the hypometabolism/hypothermia. We propose that the hypometabolism/hypothermia is a regulated response, potentially beneficial during extreme physiologic stress.Entities:
Mesh：
Substances：
Year: 2014 PMID： 24981835 PMCID： PMC4126889 DOI： 10.1016/j.cmet.2014.05.021
Source DB: PubMed Journal: Cell Metab ISSN： 1550-4131 Impact factor: 27.287