Endogenous rhythms of melatonin, total antioxidant status and superoxide dismutase activity in several tissues of chick and their inhibition by light

• Published in: Journal of pineal research Vol. 30; no. 4; pp. 227 - 233
• Main Authors: Albarrán, M.T., López-Burillo, S., Pablos, M.I., Reiter, R.J., Agapito, M.T.
• Format: Journal Article
• Language: English
• Published: Copenhagen Munksgaard 01.05.2001; Blackwell
• Subjects: Animals; Antioxidants - metabolism; Biological and medical sciences; Cerebral Cortex - metabolism; Chickens - blood; Chickens - metabolism; chicks; Chronobiology; circadian rhythms; Fundamental and applied biological sciences. Psychology; Light; Liver - metabolism; Lung - metabolism; Male; melatonin; Melatonin - blood; Melatonin - metabolism; Periodicity; Photoperiod; superoxide dismutase (SOD); Superoxide Dismutase - metabolism; Tissue Distribution; total antioxidant status (TAS); Vertebrates: anatomy and physiology, studies on body, several organs or systems; Melatonin; Enzyme; Lung; Central nervous system; Superoxide dismutase; EC 1.15.1.1; Biological rhythm; Circadian rhythm; Antioxidant; Respiratory system; Kidney; Vertebrata; Urinary system; Endogenous rhythm; Chicken; Oxidoreductases; Aves; Pineal hormone; Brain (vertebrata)
• ISSN: 0742-3098; 1600-079X
• DOI: 10.1034/j.1600-079X.2001.300406.x

Melatonin was recently shown to be a component of the antioxidative defense system of organisms due to its free radical scavenging ability and to its capacity to stimulate several antioxidant enzymes. In this report, we studied the endogenous rhythm of the antioxidant enzyme superoxide dismutase (SOD) in three different tissues (cerebral cortex, liver and lung) of chick (Gallus domesticus) (three weeks, at age and sacrificed every 2 hr). During the study the chicks were under a light:dark cycle of 12:12. Total antioxidant status of the plasma was correlated with physiological blood melatonin concentrations. Superoxide dismutase activity exhibited a marked 24 hr rhythm in cerebral cortex, lung and liver, with peak activity coincident with the melatonin and total antioxidant status peaks. The exposure of chicks to constant light for 7 days eliminated the melatonin rhythm as well as the peaks in superoxide dismutase activity and the total antioxidant status. These findings suggest that the melatonin rhythm may be related to the nighttime increase in the superoxide dismutase activity and to total antioxidant capacity of the blood.