Level of glucocorticoid hormones in early postnatal ontogenesis and circadian rhythms of endocrine-metabolic functions in adult rats.

The disturbance of the glucocorticoid balance in early postnatal ontogenesis (17-19 days) as the result of prednisolone administration has been shown to lead to partial suppression of circadian adrenocortical activity in adult rats. The circadian rhythm of FFA in these groups of animals was not detectable and the circadian acrophase of blood glucose concentration changed, while diurnal urine periodicity remained unchanged. The diurnal rhythm of locomotor activity in prednisolone-pretreated rats was characterized by a later onset of increase in its activity and a shorter duration.