Referenced in: none

Automatically associated channels: Kir6.2

Title: Central pipecolic acid increases food intake under ad libitum feeding conditions in the neonatal chick.

Authors: Tomo Takagi, Tetsuya Tachibana, Ei-Suke Saito, Shouzou Tomonaga, Shin Saito, Takashi Bungo, D Michael Denbow, Mitsuhiro Furuse

Journal, date & volume: Neurosci. Lett., 2003 Aug 21 , 347, 93-6

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/12873736

Abstract
It has been demonstrated that L-pipecolic acid (L-PA) is a major metabolic intermediate of L-lysine in the mammalian and chicken brain. A previous study showed that intracerebroventricular (i.c.v.) injection of L-PA suppressed feeding in neonatal chicks, and the actions were associated with gamma-aminobutyric acid (GABA)-B receptor activation. It has been reported that endogenous L-PA in the brain fluctuated under different feeding conditions. In the present study, we investigated the effect of i.c.v. injection of L-PA on food intake in the neonatal chick under ad libitum feeding conditions. The food intake was increased by 0.5 or 1.0 mg L-PA under ad libitum feeding conditions contrary to previous studies using fasted birds. A hyperphagic effect of L-PA (0.5 mg) was attenuated by both GABA-A receptor antagonist (picrotoxin, 0.5 microg) and GABA-B receptor antagonist (CGP54626, 21.0 ng). These results indicate that a hyperphagic effect of L-PA is mediated by both GABA-A and GABA-B receptors and L-PA differentially affects food intake under different feeding conditions in the neonatal chick.