Hypothalamic cocaine-amphetamine regulated transcript (CART) is regulated by glucocorticoids.
Cocaine-amphetamine-regulated transcript (CART) is one of the most abundantly expressed mRNAs in the rat hypothalamus. CART mRNA expression in the arcuate nucleus has been shown to be regulated by leptin, and CART peptides have been implicated in feeding behavior and in the regulation of the HPA-axis. To more fully understand the physiological regulation of CART gene expression, we have examined the effects of adrenalectomy and different types of glucocorticoid substitution (corticosterone and dexamethasone) on hypothalamic CART and POMC mRNA levels. In situ hybridization revealed a reduction in CART mRNA levels in both the hypothalamic paraventricular and arcuate nuclei in adrenalectomized rats, which was fully restored upon dexamethasone treatment but not by a subcutaneous 25% corticosterone pellet. Unlike CART mRNA levels hypothalamic POMC expression was unaltered by adrenenalectomy. The present results show that the CART gene is influenced by glucocorticoids, presumably via a GR dependent mechanism.
Vrang
Niels
N
Rheoscience, Glerupvej 2, 2610, Rodovre, Denmark. nv@ccbr.dk
Larsen
Philip J
PJ
Tang-Christensen
Mads
M
Larsen
Leif Kongskov
LK
Kristensen
Peter
P
D000315:Adrenalectomy; D000818:Animals; D005786:Gene Expression Regulation / Q000187:drug effects* / Q000502:physiology*; D005938:Glucocorticoids / Q000378:metabolism* / Q000494:pharmacology; D007031:Hypothalamus / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D009419:Nerve Tissue Proteins / Q000096:biosynthesis*; D011333:Pro-Opiomelanocortin / Q000378:metabolism / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D000098882:Cocaine- and Amphetamine-Regulated Transcript Protein
D005938:Glucocorticoids; D009419:Nerve Tissue Proteins; D000098882:Cocaine- and Amphetamine-Regulated Transcript Protein; D011333:Pro-Opiomelanocortin