BIOL 1840U Lecture Notes - X-Linked Adrenal Hypoplasia Congenita, Hypokalemia, Hyperkalemia
Document Summary
Ii: cortex derived from mesoderm along with gonads & kidneys, medulla derived from neural crest cells (migrate in after cortex cells begin to differentiate, zones of cortex during development: 1. fetal zone very large, inner zone that begins to involute at birth. Adrenal cortex: steroidogenesis, are all steroid hormones; synthesized from precursor cholesterol, cholesterol is stored in large quantities in cortex cells. 2. finished hormones are not stored => diffuse immediately: steps in steroidogenesis. 1. transport into mitochondria via star (steroidogenic acute regulatory protein: cholesterol pregnenolone via scc (side-chain cleavage enzyme) **rate limiting step** 1: multiple enzymatic reactions in mitochondria & ser => final product steroid hormones. 2: hyperkalemia powerful stiulus for synthesis, depolarizes plasma mem. => they"re the only true androgens: shbg (sex-hormone binding globin) serum binding protein for androgens, aromatase expressed by some peripheral tissues & converts testosterone to estrogens (ovarian granulosa cells)
