Endocrine System

• Thyroid Gland Function


  Produces Thyroid Hormone
• Function Of Thyroid Hormone

  Growth development, metabolism. regulates growth
• Types of Thyroid Hormone

  T3 - Triiodothyronine

  T4 - Thyroxine
• triiodothyronine function


  More powerful hormone
• Thyroxine Function


  Converts to T3 at target tissue
• Thyroid Negative Feedback System

  Hypothalamus - anterior pituitary - thyroid
• Parathyroid Gland Function


  Produces parathyroid hormone
• Parathyroid Hormone


  Secreted when calcium levels drop and stimulates osteoclasts and eats bone to increase calcium level
• Thyroid Deficiency


  Hypothyroidism - Not enough

  Hyperthyroidism - Too much
• Hypothyroidism


  Goiter on neck
• Hyperthyroidism


  Bulging eyes, weight loss, lethargy. overactive metabolism
• Adrenal Gland


  Located ontop of kidney- produces epinephrine & norepinephrine
• Adrenal Gland Order


  Medulla - Cortex - Capsule
• Adrenal Cortex contains


  Zona Reticularis innermost

  Zona Fasciculata - middle

  Zona Glomerulosa - outer most
• Hormone response


  Hypothalamus signals release of corticotropin releasing hormone - Stimulates pituitary gland release of adrenocorticotropic. ACTH reacts with adrenal cortex
• ACTH On Glomerulosa


  Release mineralocorticoids - Aldosterone
• Aldosterone


  Nephrons - function units of kidneys

  Function - filtering, reabsorbing secretory product , controls BP - kidneys reabsorb water and sodium back into blood
• ACTH On Fasciculata


  Release Glucocorticoids - cortisol
• Cortisol


  Causes Negative Feedback - causes hyperglycemia - increase infection and supressed immune responce
• ACTH on Reticularis


  Release Androgens
• Androgens


  Promotes prostate growth & Masculine characteristics. Decrease in androgens - decrease sex drive
• Pancreas


  Endocrine & Exocrine Glands

  Alpha Cells - Glucagon

  Beta Cells - Insulin
• Glucagon liver affects


  Glycogenolysis - breakdown of glycogen to glucose

  Gluconeogenesis - synthesis of glucose form a range of carbs release of glucose in blood
• Effects of insulin


  Lowers blood glucose, activate receptors at target tissue
• Homeostatic Imbalance


  Type 1 - Body targets own beta cells - inability to excrete insulin

  Type 2 - Receptors on tissue do not work
• Pineal Gland


  Pinecone like shape, singular. on midline of brain

  secretes melatonin - regulates circadian rhythm
• Pinealocytes


  Secretes Melatonin in a 24 hour cycle - highest at night

  Regulated by Retina
• Atrial Natrurietic Peptide


  Fluid Volume change blood volume BP

  Hormone ANP is secreted by atria of heart in response to blood volume