Appendix D: Endocrine Organs and Hormone Endocrine Organs and Hormones Hypothalamus “Below the thalamus”. Regulates the autonomic nervous system via the endocrine system. The four F’s. GnRH: Gonadotropin-Releasing Hormone. Stimulates the release of FSH and LH. GHRH: Growth Hormone-Releasing Hormone. Stimulates the release of GH. TRH: Thyrotropin-Releasing Hormone. Stimulates the release of TSH. CRH: Corticotropin-Releasing Hormone. Stimulates pituitary synthesis of ACTH. PIF or A catecholamine. As a neurotransmitter, most rewards will increase Dopamine: the level of dopamine. ADH and Produced in the hypothalamus; released from the posterior pituitary. Oxytocin: FSH: Follicle-Stimulating Hormone. A gonadotropin. In males it promotes spermatogenesis. In females it stimulates growth of ovarian follicles. LH: Luteinizing Hormone. A gonadotropin that induces ovulation. ACTH: Adrenocorticotropic Hormone. Stimulates the production and release of cortisol. TSH:Thyroid-Stimulating Hormone. Stimulates the Thyroid to produce Thyroxine (T4) and Triiodothyronine (T3), which stimulates metabolism. Prolactin: Stimulates milk production. Endorphins: ¯Pain Growth Also known as somatotropin. Stimulates growth and cell Hormone: reproduction. Pancreas A large gland behind the stomach. It secretes digestive enzymes into the duodenum. Embedded in the pancreas are the islets of Langerhans which secrete insulin and glucagon into the blood. Insulin: Peptide hormone secreted by b-islet cells. Its function is to help glucose enter the cells. "Glucose triggers insulin secretion. Inhibited by norepinephrine. Glucagon: Peptide hormone secreted by a-islet cells. Its function is to help glucose enter the blood stream. ¯Glucose triggers glucagon secretion. Somatostatin: Growth Hormone-Inhibiting Hormone. A peptide hormone (GHIH) secreted by d-islet (delta) cells. Inhibits GH and also leads to ¯insulin and ¯glucagon. Posterior Pituitary Posterior lobe of the pituitary gland. ADH: Antidiuretic Hormone. A peptide hormone synthesized in the (Vasopressin) hypothalamus and released by the posterior pituitary. It regulates the tonicity of body fluids. ADH is released in response to hypertonicity and causes the kidneys to reabsorb H2O. Results in concentrated urine and reduced urine volume. Can also "BP. Oxytocin: A peptide hormone synthesized in the hypothalamus and released by the posterior pituitary. During childbirth, it increases uterine contractions and is released in response to cervix stretching. Also increases milk production and certain bonding behaviors. Thyroid Gland Gonads A gland that produces gametes (sex cells) and sex hormones. In males, the gonads are testicles, in females they are ovaries. Testosterone: Anterior Pituitary Anterior lobe of the pituitary gland. It regulates several physiological processes including stress, growth, reproduction, and lactation. Produced by the testes in men and ovaries in women with a small amount produced by the Adrenal Cortex. In males, it is the primary sex hormone and an anabolic steroid. Estrogen: Produced by the ovaries. It is the primary female sex hormone and leads to the development of secondary sexual characteristics. Estrogen also regulates the menstrual cycle. ¯milk production. In the neck and below the Adam’s Apple. Secretes thyroid hormones that regulate metabolism. Also helps regulate calcium homeostasis. T4 & T3:Thyroxine (T4) and Triiodothyronine (T3). T4 is a precursor to T3. Regulates metabolism. Created from Iodine and Tyrosine. Calcitonin: Builds bone "Ca2+ in bone "Ca2+ excretion from kidneys ¯Ca2+ in blood ¯Ca2+ absorption in gut Progesterone: Produced by the ovaries. Prepares the endometrium for potential pregnancy following ovulation. ¯milk production Parathyroid Glands Pineal Gland A collection of 4 parathyroid glands located on the back of the thyroid. Primary function is to maintain the body’s Ca 2+ and K+ levels so that the nervous and muscular systems can function properly. Located in the epithalamus, tucked into a groove between the two thalamus halves. Melatonin: Regulates sleep / wakefulness and controls the circadian rhythm. Adrenal Cortex Sits along the perimeter of the adrenal gland (top of kidney). Mediates stress response. Glucocorticoids: Cortisol is released during stress. "Glucose in blood through gluconeogenesis ¯Immune system ¯Protein synthesis Cortisone is similar to Cortisol. ¯Immune response so ¯inflammation and ¯allergic response Mineralcorticoids: Aldosterone causes "Na+ in blood which "BP. It is regulated by K+ and angiotensin II which is derived from angiotensin I. Androgens: Converted to Testosterone and Estrogen in the gonads. PTH: Parathyroid Hormone. Bone breakdown. ¯Ca2+ in bone ¯Ca2+ excretion from kidneys "Ca2+ in blood "Ca2+ absorption in gut Activates Vitamin D (Calcitriol) Adrenal Medulla Sits on top of the kidney. Adrenal Medulla is located at the center of the adrenal gland, surrounded by the adrenal cortex. It converts tyrosine into catecholamines. Epinephrine: "HR and "BP. Primarily a hormone. Also an anti-histamine. Norepinephrine: "HR and "BP. A hormone and a neurotransmitter; inhibits insulin. Dopamine: The adrenal medulla secretes a small amount of dopamine.