Local transfer of hormones between blood vessels within the adrenal gland may explain the functional interaction between the adrenal cortex and medulla.
The adrenal cortex has a local stimulatory action on synthesis and secretion of adrenaline by the adrenal medulla. This interaction may be based on nervous transmission and/or on glucocorticoids secreted trom the cortex either exerting paracrine effects or reaching the medulla through the local vascular system. The existence of a dual capillary network, a portal system, now seems unlikely. However, a new concept is postulated: the high demand for glucocorticoids in the medulla may be met by local transfer to blood vessels within the adrenal gland, particularly the medullary arteries.
D000302:Adrenal Cortex / Q000098:blood supply / Q000502:physiology*; D000311:Adrenal Glands / Q000098:blood supply*; D000313:Adrenal Medulla / Q000098:blood supply / Q000502:physiology*; D000818:Animals; D002196:Capillaries / Q000033:anatomy & histology / Q000502:physiology*; D004837:Epinephrine / Q000378:metabolism; D005938:Glucocorticoids / Q000097:blood / Q000502:physiology; D006728:Hormones / Q000097:blood / Q000502:physiology*; D006801:Humans; D008954:Models, Biological
D005938:Glucocorticoids; D006728:Hormones; D004837:Epinephrine