[Stress-hyperresponsive period in postnatal development of hypothalamic-hypophyseal-adrenal system in mice]

to compare response to stress, activity of adenylatcyclase and enzymes of steroidogenesis in adrenal cells in 3-week and adult (15-week) mice. In 3-week mice, basal and stressor level of blood corticosterone was increased. Their response to stress was faster developing as compared with adult mice. In vitro, 3-week mice had enhanced adrenal sensitivity to ACTH, corticosterone release in response to ACTH, exogenous cAMP and progesterone; and the cAMP level in the cells stimulated with ACTH and forscoline. Thus, in 3-week mice, a stress-hyperresponsive period occurs due to increased release of corticosterone and adrenal sensitivity to ACTH. The reason of this involves enhanced activity of adenylatcyclase and intracellular enzymes of steroidogenesis.