Developmental pattern of ornithine decarboxylase activity, S-adenosylmethionine decarboxylase, and polyamines of rat adrenal glands.

The concentrations of polyamines and the activities of ornithine decarboxylase (ODC) and of S-adenosylmethionine decarboxylase (SAM-DC) were measured in the adrenal glands of rats during development. Adrenal spermine content increases gradually during the first month of life whereas spermidine and putrescine decrease. A low spermidine/spermine ratio is obtained. The developmental pattern of adrenal SAM-DC resembles that of spermine content. The activity of adrenal ornithine decarboxylase increases after birth and attains a peak at 17 days of age. It declines sharply thereafter. Induction of adrenal ODC following the stress of immobilization is already observed in the rat at 4 days of age but the induction caused by maternal deprivation or cold exposure is obtained only at 17 days. The results suggest that the developmental pattern of ODC activity is independent of its responsivity to various stressors.