第8回日本ステロイドホルモン学会

An isolated adrenocortical cell deprived of its tissue integrity, input from the nervous system , or intercellular communication with chromaffin, vascular, and immune cells of the adrenal gland, loses its normal capacity to produce glucocorticoids and to adequately respond to the homeostatic challenges of stress.We have recently shown that adrenocortical cells in co-culture with chromaffin cells produce ten times more glucocorticoids than the same number of pure adrenocortical cells and demonstrate a marked up-regulation in the mRNA expression of cytochrome p450 enzymes in co-culture, while this expression is down-regulated in isolated cells.Transgenic animal models of over-expression or deletion of enzymes involved in catecholamine synthesis, as well as of altered function of components of the HPA axis, provide evidence that the mutual interdependence of the sympatho-adrenal system and the HPA axis at the level of the adrenal gland is of physiologic relevance in vivo .1 Based on a thorough understanding of these