Central L-ornithine, but not polyamines, induces a hypnotic effect in neonatal chicks under acute stress.
To clarify whether L-ornithine and/or its metabolite involves sedative and hypnotic effects under social separation stress, the effects of intracerebroventricular (i.c.v.) injection of L-ornithine and polyamines (putrescine, spermidine and spermine) were compared in chicks. Birds were injected i.c.v. with 0.5 mumol of L-ornithine, putrescine, spermidine, spermine or saline (control). After injection, chicks were immediately separated from the flock and monitored for the number of distress vocalizations and various postures. L-Ornithine greatly attenuated the stress response and caused sedative and hypnotic effects. Among the polyamines, only putrescine attenuated distress vocalizations but did not induce sleep. In conclusion, the sedative and hypnotic effect of L-ornithine was mainly induced by L-ornithine itself, while the polyamines contributed to the sedative, but not hypnotic, effect under social separation stress.
Laboratory of Regulation in Metabolism and Behavior, Graduate School of Bioresources and Bioenvironmental Sciences, Kyushu University, Fukuoka, Japan.
Isao
I
Kurauchi
Kazutaka
K
Shigemi
Yusuke
Y
Kabuki
Kousuke
K
Hamasu
Haruka
H
Yamane
Mami
M
Aoki
Yoko
Y
Kawada
Koji
K
Morishita
D Michael
DM
Denbow
Mitsuhiro
M
Furuse
D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects; D002645:Chickens; D006993:Hypnotics and Sedatives / Q000008:administration & dosage / Q000378:metabolism / Q000494:pharmacology*; D007276:Injections, Intraventricular; D008297:Male; D009952:Ornithine / Q000008:administration & dosage / Q000378:metabolism / Q000494:pharmacology*; D011073:Polyamines / Q000008:administration & dosage / Q000494:pharmacology*; D011187:Posture; D011700:Putrescine / Q000008:administration & dosage / Q000494:pharmacology; D012934:Social Isolation; D013095:Spermidine / Q000008:administration & dosage / Q000494:pharmacology; D013096:Spermine / Q000008:administration & dosage / Q000494:pharmacology; D013315:Stress, Psychological / Q000188:drug therapy*; D013997:Time Factors; D014828:Vocalization, Animal / Q000187:drug effects
D006993:Hypnotics and Sedatives; D011073:Polyamines; D013096:Spermine; D009952:Ornithine; D013095:Spermidine; D011700:Putrescine