Lack of direct action of D-fenfluramine on arcuate preproNPY mRNA levels in the rat.
Hypothalamic neuropeptide Y (NPY) and 5-hydroxytryptamine (5-HT) may interact to regulate food intake. This study investigated the effects of the 5-HT reuptake blocker and secretagogue D-fenfluramine (D-FEN) on preproNPY mRNA abundance in the hypothalamic arcuate nucleus (ARC) of free-feeding and food-deprived (FD) rats in two treatment regimens. ARC preproNPY mRNA levels were significantly increased in FD rats, to the same extent as in combined FD/D-FEN animals. D-FEN treatments producing different-sized reductions in food intake (and body weight) produced corresponding changes in ARC preproNPY mRNA abundance. These findings suggest that ARC preproNPY mRNA levels are not directly altered by D-FEN, and that D-FEN-induced anorexia does not involve effects on the hypothalamic NPY system at the level of NPY gene transcription.
O'Shea
R D
RD
University of Melbourne, Department of Medicine, Austin and Heidelberg Repatriation Hospitals, Vic., Australia.
Gundlach
A L
AL
D000818:Animals; D001111:Arcuate Nucleus of Hypothalamus / Q000187:drug effects* / Q000378:metabolism; D001835:Body Weight / Q000187:drug effects; D004435:Eating / Q000187:drug effects; D005277:Fenfluramine / Q000494:pharmacology*; D008297:Male; D009478:Neuropeptide Y / Q000235:genetics*; D011498:Protein Precursors / Q000235:genetics*; D012333:RNA, Messenger / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley
D009478:Neuropeptide Y; D011498:Protein Precursors; D012333:RNA, Messenger; D005277:Fenfluramine; C042084:preproneuropeptide Y