advanced pathophysiology NR 507 final exam

Fat Soluble Hormones - Steroids Water Soluble Hormones - Need 2nd Messenger to transport across phospholipid membranes Pituitary Hormones - TSH, GH, ACTH, FSH, LH, Oxytocin, ADH, Melanocyte Stimulating Hormone Anterior Pituitary - Acct for 75% of total weight of pituitary gland. Three regions, pars distalis, parts tuberalis, and pars intermedia. Pars distalis is major component of Anterior Pituitary and source of Anterior Pituitary Hormones. Posterior Pituitary (neurohypophysis) - Arises from 3rd ventricle of brain, consists of three parts, median eminence, pituitary stalk, and infundibular process (pars nervosa or neural tube). Median eminence is composed mainly of nerve endings of axons that arise primarily from ventral hypothalamus. Hypothalamic releasing Hormones in Posterior pituitary's median eminence. - Includes 10 hypothalamic releasing hormones and neurotransmitters such as dopamine, norepinephrine, serotonin, acetylcholine, and histamine. Pituitary stalk - contains axons of neurons that originate in the supraoptic and paraventricular nuclei of the hypothalamus. Hormones of posterior pituitary - ADH, and Oxytocin (Peptide Hormones) ADH (antidiuretic Hormone) - Major homeostatic function of posterior pituitary is control of plasma osmolality, as regulated by ADH Hypothalamic hormones and target tissues (Hypophysiotropic hormones) - HORMONES: Thyrotropin Releasing Hormone (TRH), Gonadotropoin-releasing hormone (GnRH), Somatostatin, Growth hormone-releasing hormone (GHRH), corticotropin-releasing hormone (CRH), Substance P, Dopamine, Prolactin-releasing factor. TARGET Tissue: Anterior Pituitary Somatostatin - Inhibits release of growth hormone and TSH Gonadotropoin-releasing hormone - Stimulates release of FSH and LH Dopamine - Inhibits synthesis and secretion of prolactin Prolactin-releasing factor (PRF) - Stimulate secretion of prolactin Tropic Hormones of Anterior Pituitary and their function - ACTH, Melanocyte-stimulating Hormone (MSH, Somatotropic hormones, GH, prolactin, LH, TSH, FSH, glycoprotein hormones Adrenocorticotropic hormone (ACTH) - SECRETORY CELL TYPE: Corticotropic TARGET ORGANS: Adrenal Gland (cortex) FUNCTIONS: Increased steroidogenesis (cortisol, and androgenic hormones Prolactin, - Milk production TSH - Increased production and secretion of thyroid hormone Luteinizing Hormone (LH) - Ovulation, progesterone production (in glanulosa cells) Follicle Stimulating Hormone (FSH) - Follicle maturation, estrogen production (In Women: Granulosa Cells, In Men: Sertoli Cells) B-Lipotropin - Fat breakdown and release of fatty acids (Corticotropic, from Adipose Cells) B-Endorphins - Analgesia; may regulate body temp, food and water intake (Corticotropic, Adipose cells, brain opioid receptors) ADH functions - Homeostasis, control plasma osmolality. Acts of Vasopressin 2 (V2) receptors of renal tubular cells to increase permeability which leads to increased water reabsorption into the blood and production of more concentrated urine, these may be inhibited by hypercalcemia, prostaglandin E, and hypokalemia.