Melatonin enhances NADPH-diaphorase activities in the hypothalamus of maternally-separated rats.
Maternal separation or social isolation is a risk factor in the development of mammalian species affecting both physical and mental growth, and food intake regulation. Melatonin has been known to regulate body weight on various species including rodents. We investigated the effect of melatonin treatment on the expression of nitric oxide synthase, which may involved in food intake regulation, in the brain of maternally separated-rats using nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d) histochemistry. Melatonin (10 mg/kg i.p.) was injected to 14-day-old maternally-separated rats for 7 days. Maternally-separated rats with melatonin administration showed significantly higher staining intensities of NADPH-d-positive neurons in the paraventricular nucleus (PVN) and in lateral hypothalamic area (LHA) than maternally-separated without melatonin administration (P < 0.05). Body weight of melatonin treated rats significantly increased at the 6th and 7th day compared to that of rats without melatonin treatment (P < 0.05). These results indicate that melatonin may be associated with increase body weight via NOS in the hypothalamic areas in maternally-separated or socially isolated rats.
Kim
Mi-Ja
MJ
Department of Obesity Management, Graduate School of Obesity Science Dongduk Women's University, Seoul, South Korea.
Kim
Young-Ok
YO
Chang
Un-Jae
UJ
Kim
Hye-Kyung
HK
Chung
Joo-Ho
JH
Oh
Dong-Jae
DJ
Kim
Jong-Woo
JW
D000818:Animals; D000831:Animals, Newborn; D001835:Body Weight / Q000187:drug effects; D002452:Cell Count; D005260:Female; D006651:Histocytochemistry / Q000379:methods; D007031:Hypothalamus / Q000166:cytology / Q000187:drug effects*; D008297:Male; D008426:Maternal Deprivation; D008550:Melatonin / Q000494:pharmacology*; D009252:NADPH Dehydrogenase / Q000378:metabolism*; D009474:Neurons / Q000187:drug effects / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors
D009252:NADPH Dehydrogenase; D008550:Melatonin