[The effect of neonatal nutrition on lipolysis and catecholamine binding in rat adipocytes]

Underfeeding or overfeeding of rats during the suckling period, realized by the adjustment of the number of sucklings per litter, are followed by important changes in the function of endocrine glands and hormonal stimulation of lipolysis in adipocytes. For explanation of causes of the differences in the stimulation of lipolysis the changes of beta-receptors in adipocytes were studied in animals with different neonatal nutrition. The number of suckling pups in litter was adjusted to 4, 8, 14 on the second postnatal day. After weaning (at the age of 30-500 days) the size of adipocytes, basal and norepinephrine stimulated lipolysis, the binding of 3H-dihydroalprenolol in adipocytes were determined. In neonatally underfed animals, in comparison to overfed, those a decrease in the size of adipocytes, a diminution of basal lipolysis and lower stimulation of lipolysis by norepinephrine were observed. The decrease in binding capacity (at the age of 30-60 days) and of affinity of beta-receptors (at the age of 60 to 360 days) were found in neonatally overfed rats. These results showed that the changes of beta-adrenergic receptors in adipocytes of animals with neonatal nutritions have a role in the alteration of the stimulation of lipolysis in adipocytes. (Tab. 2, Fig. 4, Ref. 29.).