PHRM 211 Lecture Notes - Lecture 5: Anterior Pituitary, Circadian Rhythm, Dehydroepiandrosterone
Document Summary
Divided into medulla (epinephrines) and cortex (corticosteroids) Male: adrenal become major source of androgens with age. Hypothalamus produces crh and vasopressin (act on anterior pituitary) Anterior pituitary produces acth (acts on adrenal gland) Cortisol has negative feedback on all pieces of the axis. Midnight nadir (lowest point) (with established day-night sleep routine) Moa : binds to glucocorticoid receptor and alters gene transcription. Prednisone and cortisone are prodrugs and require hepatic activation. Cortisone hydrocortisone t1/2 vary depending on protein-binding affinity and side chains. Adverse effects: htn, cataracts, edema, peptic ulcers, alopecia, acne, osteoporosis. Dexamethasone has the highest relative glucocorticoid activity (highest dose). Requires acidic environment for absorption (antacids/ppi/h2ra decrease absorption) Strong inhibitor of cyp enzymes (many drug-drug interactions) Cortisol: headache, sedation, fatigue, decreased appetite, n/v, orthostatic hypotension, adrenal insufficiency. Interactions drugs that undergo cyp enzyme metabolism. Inhibits cyp11b1 mediate conversion of 11-deoxycortisol to cortisol. Inhibits aldosterone synthase (and production of another mineralocorticoid)
