ENDOCRINE SYSTEM

STRUCTURES  Group of ductless glands that secrete substances directly into the blood stream.  Substances are known as hormones  Hormones are substances that are frequently referred to as “chemical messengers” that stimulate many functions through out the body.  Functions include: Stimulate exocrine glands, stimulate other endocrine glands, Regulate growth and development, Regulate metabolism, Maintain fluid and chemical balance, Control various sex processes

STRUCTURES  Pituitary Gland  Often called master gland because it produces many hormones that affect other glands.  Located at the base of the brain  Separated into two lobes both secrete different hormones  Anterior Lobe: Somatotropin-Growth Hormone, Follicle Stimulating/Luteinizing- Ovulation/Sperm production, Prolactin- production of milk, Melanocyte Stimulating- Stimulates production and dispersion of melanin pigment in the skin  Posterior Lobe-Vasopressin-antidiuretic, promotes reabsorption of water in the kidneys and constricts vessels, Oxytocin-Causes contraction of uterus during childbirth, stimulates milk flow from the breast

PITUITARY GLAND

STRUCTURES  Thyroid Gland  Sits on anterior aspect of trachea  Secretes: Thyroxine-stimulates metabolic rate, physical and mental growth, regulates metabolism of carbohydrates, proteins and fats, Calcitonin- absorption of calcium by the bones and lowers blood calcium levels

THYROID GLAND

STRUCTURES  Parathyroid Gland  Sits on top of thyroid gland  Secretes-Parathormone-Regulates the amount of calcium and phosphate in the blood, stimulates kidneys to conserve blood calcium, stimulates calcium absorption in the small intestine

PARATHYROID GLAND

STRUCTURES  Adrenal Gland  Sits on top of both kidneys  Secretes-Mineralocorticoids-reabsorption of sodium, potassium and water in the kidneys, Glucocorticoids-metabolism of nutrients, increase blood glucose levels, reduce stress and anti-inflammatory, Gonadocorticoids-stimulates either male or female sexual characteristics, Epinephrine-stimulates sympathetic nervous system, fight or flight response, Norepinephrine- Fight or flight response

ADRENAL GLAND

STRUCTURES  Pancreas  Sits below stomach in upper left quadrant  Secretes: Insulin-Metabolism of glucose, promotes fatty and amino acid transport into cells, Glucagon-Maintains blood level of glucose by stimulating the liver to release stored glycogen

PANCREAS

STRUCTURES  Ovaries  Found in women sit deep inside the body cavity at the top of the uterus  Secrete: Estrogen-promotes growth and development of sex organs, Progesterone-Maintains lining of the uterus

OVARIES

STRUCTURES  Testes  Found in males located in the scrotum that hangs from the body  Secretes: Testosterone-Stimulates growth of male sex organs and maturation of sperm

TESTES

STRUCTURES  Thymus  Sits center of chest in children  Disappears during puberty  Secretes: Thymosin-stimulates production of lymphocytes and antibodies in early life

THYMUS

STRUCTURES  Pineal  Located in brain  Secretes: Melatonin-may delay puberty by inhibiting gonadotropin, may regulate sleep/wake cycles, Serotonin-may prevent vasoconstriction in the brain, inhibits gastric secreations

PINEAL GLAND

DISEASES AND CONDITIONS Acromegaly Over secretion of somatotropin causes a benign tumor on the pituitary gland. Bones of the hands, feet and face enlarge, skin and tongue thickens causing slurred speech Treatment is surgical removal of tumor or radiation, however tumor usually returns Shortens life expectancy

DISEASE AND CONDITIONS  Gigantism  Over secretion of somatotropin before puberty  Excessive growth of long bones, extreme tallness, decreased sexual development

DISEASES AND CONDITIONS  Diabetes Insipidus  Decreased secretion of vasopressin  Results in water failing to be reabsorbed by the kidneys  Increases urination, excessive thirst, dehydration, weakness, constipation and dry skin  Administer ADH to correct

DISEASES AND CONDITIONS  Dwarfism  Under secretion of somatotropin and can be causes by a tumor, infection genetic factors or injury  Small body size, short extremities, lack of sexual development  Can be treated if caught early with injections.

DISEASES AND CONDITIONS  Goiter  Enlargement of the Thyroid Gland  Causes: hyperactive thyroid, iodine deficiency, tumor, over secretion of thyroid stimulating hormone in the pituitary gland  Thyroid enlargement, difficulty swallowing, cough, choking sensation  Treatment is to eliminate the cause

DISEASES OR CONDITIONS  Hyperthyroidism  Over activity of the thyroid gland which increases BMR  Symptoms: extreme nervousness, tremors, irritability, rapid pulse, excessive sweating, heat intolerance  Treatment: radiation or surgical intervention

DISEASES AND CONDITIONS  Hypothyroidism  Under activity of the thyroid gland  Two types Cretinism or Myxedema  Symptoms: course dry skin, slow mental function, fatigue, weakness, intolerance to cold, weight gain, edema, puffy eyes, slow pulse

DISEASES AND CONDITIONS  Graves Disease  Extreme form of hyperthyroidism  More common in women than men  Symptoms include: strained tense facial expressions, protruding eyeballs, goiter, emotional instability, tachycardia, tremendous appetite with weight loss  Treatment: medication, radiation and surgical removal

DISEASES AND CONDITIONS  Hyperparathyroidism-over production of parathormone due most often to tumor  Symptoms: excessive calcium in blood, kidney stones, lethargy, gastrointestinal issues, calcium deposits in vessels and organs  Treatment: Removal of tumor, removal of glands, diuretics, low calcium diet

DISEASES AND CONDITIONS  Hypoparathyroidism-Underactivity of the parathyroid, causes low levels of calcium in the blood.  Symptoms: Constant contraction of muscles, hyperirritability of nervous system, twitching possible death  Treatment: Supplement calcium and vitamin d, surgical removal of parathyroid glands

DISEASES AND CONDITIONS  Addison’s Disease-decreased secretion of aldosterone by adrenal glands, interferes with reabsorption of sodium and water resulting in high potassium levels in the blood  Symptoms: dehydration, diarrhea, fatigue, hypotension, mental lethargy, weight loss, excessive pigmentation (bronzing of the skin)  Treatment: corticosteroids, control sodium intake, fluid regulation

DISEASES AND CONDITIONS  Cushing’s Disease-Over secretion of glucocorticoids from the adrenal glands, caused by tumor or pituitary gland defect  Symptoms: hyperglycemia, hypertension, excessive hair growth, poor wound healing, A “moon” face, obesity  Treatment: removal of tumor/glands, hormone replacement therapy

DISEASES AND CONDITIONS  Treatment: None for Type 1, just manage symptoms through insulin, Type 2 is about weight control and exercise as well as diet corrections  Diabetes Mellitus-chronic disease caused by decreased secretion of insulin  Two types: Type 1 (insulin dependent) occurs early in life, more severe and requires insulin, Type 2 (non-insulin dependent) occurs later in life, not a severe, diet restriction  Symptoms: hyperglycemia, frequent urination, excessive thirst, sugar in urine, weight loss, slow healing skin infections, vision changes