Histamine H₄ Receptor Regulates ACTH Release From AtT-20 Cells

ACTH (Adrenocorticotropic hormone), the important messenger molecule of neuronal endocrine and immune network, is synthesized not only by neuroendocrine cells from the anterior pituitary but also synthesized and secreted by many peripheral immune cells. Via activation of ACTH receptors distributed in the membrane of immune cells in brain and peripheral tissues, it plays critical roles in various physiological procedures including neural recovery and regeneration after damage, learning and memory, and modulation of bodily immune function. Early in 1941 it was discovered that histamine stimulated ACTH secretion through the histamine receptor subtype in charge maintained being under controversy. Attributing to the newly reported discovery of histamine H₄ receptor and numerous researches on H4 receptor signaling pathway, we assume that it might be histamine H4 receptor which mediating the histamine-stimulated ACTH release from pituitary. In the present study, employing molecular biological and general pharmacological experimental methods we investigated the mechanism of histamine-stimulated ACTH release from cultured mouse pituitary tumor AtT—20 cells.1 Expression of histamine H4 receptor in AtT—20 cell line was detected...