BIOL 320 1st EditionLecture 2 Outline of Last Lecture I. Review of Epithelial Tissue Cell TypesA. DescriptionB. FunctionC. LocationII. Endocrine SystemA.Definition of EndocrinologyIII. HormonesA. DefinitionB. CategoriesC. Mechanism of ActionD. Target Cell SpecificityE. Interaction of Hormones at Target CellsF. Control of Hormone ReleaseIV. Hypothalamus and PituitaryA. Structural and Functional RelationshipOutline of Current Lecture V. Posterior Pituitary-Hypothalamic HormonesA. RegulationB. OxytocinC. Antidiuretic Hormonei. “Fun” with ADHVI. Hypothalamic HormonesA. Release To?B. TargetC. RegulationD. Description of HormonesVII. Anterior Pituitary HormonesA. RegulationB. Description of HormonesVIII. Thyroid GlandA. Location and StructureB. Thyroid HormonesC. Homeostatic ImbalancesIX. Parathyroid GlandsA. Location and StructureB. Parathyroid HormoneC. Homeostatic ImbalancesCurrent LecturePosterior Pituitary-Hypothalamic Hormones- Regulation: Neural- ADH and Oxytocin are hypothalamic hormones not pituitary hormones…posterior pituitary allows for release into bloodstream- Oxytocin- Paraventricular hypothalamic nuclei produce hormone- Released during childbirth (stimulant of uterine contractions) and in nursing women- Acts via the PIP2-Ca2+ second-messenger system- Positive-feedback loop- Antidiuretic Hormone (ADH) [or Vasopressin (AVP)]- Supraoptic hypothalamic nuclei produce hormone- Released to inhibit or prevent urine formation- Acts via the cAMP second messenger system- Targets the kidney tubules to respond by reabsorbing more water from the forming urine and returning it to the bloodstream- “Fun” with ADHo Diabetes insipidus = “Tasteless Overflow” Excessive urination (without sugar in the urine) ADH is not released Blood pressure is decreased Dehydration can occur Can be result of trauma to the head that target the supraoptic hypothalamic nucleio Breaking the Seal Once you have had to go to the bathroom the first time (while drinking alcohol), you continuously have to go. Alcohol inhibits ADH…hormonal system slow to self-adjust/correcto Hangover Result of dehydration due to decreased release of ADHVentral Hypothalamic Hormones- Released Into?o Hypophyseal portal system- Targeto Anterior pituitary (Adenohypophysis)- Regulationo Hormonal- Description of Hormoneso Growth Hormone Releasing Hormone (GHRH): Triggers the anterior pituitary to release growth hormone (GH)o Somatostatin or Growth Hormone Inhibiting Hormone (GHIH): Inhibits the anterior pituitary release of growth hormone (GH)o Thyrotropin Releasing Hormone (TRH): Triggers the anterior pituitary to release thyroid stimulating hormone (TSH or Thyrotropin)o Corticotropin Releasing Hormone (CRH): Triggers the anterior pituitary to release adrenocorticotropin hormone (ACTH)o Gonadotropin Releasing Hormone (GnRH): Triggers the anterior pituitary to release gonadotropins (LH and FSH) to reproductive structures (ovaries or testes)o Prolactin Releasing Hormone (PRH): Triggers the anterior pituitary to release prolactin for milk productiono Prolactin Inhibiting Hormone (PIH): Inhibits the anterior pituitary to release prolactinAnterior Pituitary Hormones- Regulationo Hormonal- Description of Hormoneso Growth Hormone (GH): Causes growth Highest levels during childhood Target: EVERYTHING (not just muscular & skeletal) Metabolic rate increases (amino acid uptake increases to build protein and fat burning increases) Glucose sparing (other body system use other energy sources to preserve glucose for the brain energy requirement Increases sulfur uptake for cartilage growth Protein synthesis decreases with age…muscle atrophy is a big problem unless activity is maintained Timing of sleep is critical for proper release Release is altered by stress Release changes in response to nutrient blood levelso Thyrotropin/Thyroid Stimulating Hormone (TSH): Stimulates the thyroid to synthesize and release thyroid hormone (TH)o Adrenocorticotropic Hormone (ACTH): Stimulates the adrenal cortex to synthesize steroid hormones (mineralocorticoids, glucocorticoids, and androgens)o Follicle Stimulating Hormone (FSH): Stimulate the ovaries and testes to produce hormones (estrogen & progesterone by the ovaries and testosterone by the testes…as well as other functions)o Luteinizing Hormone (LH): Stimulate the ovaries and testes to produce hormones (estrogen & progesterone by the ovaries and testosterone by the testes…as well as other functions)o Prolactin (PRL): Stimulates milk production in mammary glands Release is tied to estrogen levels (released when estrogen levels are high)Thyroid Gland- Location and Structureo Two lobed orgain joined by an isthmuso Sits on top of tracheao Well vascularizedo Histology: Follicular cells (in direct contact with the follicle) Produce thyroid hormone (T3 active form and T4 inactive form)…mostly T4  Parafollicular cells (not in direct contact with follicle) Produces calcitonin- Thyroid Hormoneso Thyroxine (T4): inactive form of TH…two tyrosines and four iodineso Triiodothyronine (T3): active form of TH…two tyrosines and three iodines Tissues take up T4 and turn it into T3  Promotes normal: Basal metabolic rate (BMR) Heart rate & blood pressure Muscle function Nervous system development and function GI motility Female reproductive function Skin conditiono Calcitonin: Decreases concentration of calcium in blood Stimulates osteoblasts to reduces calcium levels and inhibit osteoclasts activity Higher in children than adults Not necessary for proper calcium homeostasis- Homeostatic Imbalanceso Myxedema/Hypothyroidism Mucus swelling Symptoms: Low BMR Constant chills Constipation Sluggish thinking Treatment: Hormone supplement Iodine intake in diet Caused by: Insufficient iodine intake in dieto Goiter can result Dysfunction with TRH or TSH releaseo Grave’s Disease/Hyperthyroidism Symptoms: High BMR Constant sweating Anxious Exophthalmos (bulging/protruding eyeballs…due to edema in eye socket) Treatment: Surgical removal of the thyroid gland Ingestion of radioactive iodine, which selectively destroys the most active thyroid cells Caused by: Autoimmune disorder where over secretion of TH resultsParathyroid Glands- Location and Structureo