Role of serotonergic mechanisms in leptin-induced suppression of milk intake in mice.
Effects of leptin on milk consumption in food-deprived mice were investigated. In this feeding model, systemic administration of leptin reduced milk intake of mice dose-dependently. Decreases in milk intake elicited by leptin were significantly reduced by the serotonin (5-HT) synthesis inhibitor p-chlorophenylalanine (PCPA). The suppressive effects of leptin on milk intake were antagonized by the 5-HT(2B/2C) receptor antagonist SB206553, while the 5-HT(1B) receptor antagonist GR55562 and the 5-HT(2A) receptor antagonist ketanserin did not affect it. Our results indicated that the 5-HT depleter PCPA and the 5-HT(2B/2C) receptor antagonist SB206553 attenuated leptin-induced suppression of milk intake. Therefore, leptin-induced hypophagic effects may be mediated by enhancement of serotonergic neurons, resulting in activation of the 5-HT(2B/2C) receptor.
Yamada
Jun
J
Department of Pharmacology, Kobe Pharmaceutical University, Motoyamakita-machi, Higashinada-ku, 658-8558 Kobe, Japan. j-yamada@kobepharma-u.ac.jp
Sugimoto
Yumi
Y
Hirose
Hiroshi
H
Kajiwara
Yoshinobu
Y
D000818:Animals; D004305:Dose-Response Relationship, Drug; D004435:Eating / Q000187:drug effects* / Q000502:physiology; D005508:Food Deprivation / Q000502:physiology; D020738:Leptin / Q000494:pharmacology*; D008297:Male; D051379:Mice; D008892:Milk; D054411:Receptors, Leptin; D011985:Receptors, Serotonin / Q000502:physiology*; D012701:Serotonin / Q000502:physiology; D012702:Serotonin Antagonists / Q000494:pharmacology
D020738:Leptin; D054411:Receptors, Leptin; D011985:Receptors, Serotonin; D012702:Serotonin Antagonists; C515447:leptin receptor, mouse; D012701:Serotonin