Effect of food restriction on 24-h serum and pineal melatonin content in male rats.
Food restriction (50%) effects on the 24-h rhythm of serum and pineal melatonin (MT) were studied in 260-300 g male Wistar rats under a lighting regimen of 14 h light and 10 h dark. Body weight, testicular weight, accessory organ weights, serum LH, serum testosterone, and 24-h rhythms of serum and pineal MT were determined. One week of food restriction caused a decrease in body weight (18%), accessory organ weights (18%), and serum LH (50%), but had no effect on serum or pineal MT. Three weeks of food restriction suppressed the body weight and accessory organ weights further (35% and 39%, respectively), reduced serum LH (68%) and serum testosterone (53%), reduced pineal MT (12%) and raised serum MT (34%). The increased serum MT may play a role in the reported potentiation of pineal action in food deprived rats.
D000818:Animals; D001835:Body Weight; D002940:Circadian Rhythm; D005502:Food; D005837:Genitalia, Male / Q000033:anatomy & histology; D007986:Luteinizing Hormone / Q000097:blood; D008297:Male; D008550:Melatonin / Q000378:metabolism*; D009929:Organ Size; D010870:Pineal Gland / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D013739:Testosterone / Q000097:blood; D013997:Time Factors
D013739:Testosterone; D007986:Luteinizing Hormone; D008550:Melatonin