Hormones-Receptors-BostonUniversityMedicalCampus.pdf

Hormones-Receptors: Learning Objectives: (1) Define the properties of hormone-receptor interactions, (2) Choose a KD for a hormone receptor interaction and calculate the free hormone concentrations needed to achieve 10 or 90% receptor occupancy, (3) Identify the major classes of receptors and the features that distinguish them, (4) Review the G-protein cycle and the effectors that various α-subunits modifiy, (5) Give examples of the types of signaling processes that modulate cell function following hormone binding, (6) Describe the mechanism of action of steroid (and thyroid) hormones, (7) Indicate the common structural and functional properties of receptors for these hormones, (8) Describe three mechanisms by which cells can reduce their sensitivity to hormones. CHEMICAL CLASS HORMONE MAJOR SOURCE Amines Iodothyronines Small Peptides Proteins Glycoproteins Steroids Dopamine Norepinephrine Epinephrine Melatonin Thyroxine (T4) Triiodothyronine Vasopressin (ADH) Oxytocin Atrial Natriuretic Peptide Melanocyte Stimulating H. (MSH) Angiotensin II Thyrotropin Releasing H. (TRH) Gonadotropin Releasing H.(GnRH) Growth H. Releasing H. (GHRH) Corticotopin Releasing H. (CRH) Somatostatin Insulin Glucagon Growth Hormone (GH) Prolactin (Prl) Parathyroid Hormone (PTH) β-lipotropin and enkephalin Calcitonin Adrenocorticotrophic H. (ACTH) Secretin Cholecystokinin (CCK) Gastrin Gastric Inhibitory Peptide (GIP) Follicle Stimulating H. (FSH) Luteinizing H. (LH) Chorionic Gonadotropin (hCG) Thyroid Stimulating H. (TSH) Estrogens Progesterone Testosterone (T) Dihydrotestosterone Glucocorticoids Aldosterone Vitamin D metabolites CNS CNS, adrenal medulla Adrenal medulla Pineal Thyroid Peripheral tissues (thyroid) Posterior pituitary Posterior pituitary Heart Pars intermedia Blood (from precursor) Hypothalamus, CNS Hypothalamus, CNS Hypothalamus, CNS Hypothalamus, CNS Hypothal., pancreas, gut, other β-cells in pancreas α-cells in pancreas Anterior pituitary Anterior pituitary Parathyroid g