Path 2: Endocrine System

  1. Endocrine system
    • works in concrete with the nervous system to control the body
    • any disease affecting the endocrine system will therefore see effects elsewhere in the body
  2. Hormones
    • is a chemical substance produced by the body
    • a chemical messengers that travel within the circulation and act at sites where there are receptors
  3. Receptors
    receptor, or receptor site, is a structural protein molecule on the membrane of the cell or within the cytoplasm
  4. Hormonal Regulation (2)
    • Negative Feedback: maintain balance or homeostasis *(ex. thermastat in your home, regulating the temperature)
    • Positive Feedback: the initial stimulus results in a response that enhances the effect of the stimulus (ex. Pitocin "jumps" your body into faster labor before your tissues are ready)
  5. Endocrine Diseases
    • Excessive Secretion of Hormones:
    • 1. Primary hyperfunction: Problem with the gland or organ itself/hyperplasia or neoplasia
    • 2. Secondary hyperfunction: Problem with a separate organ or gland

    • Decreased Secretion of Hormones
    • 1. Primary hypofunction: congenital abscence, hypoplasia, destruction of gland, or neoplasms (cancer)
    • 2. Secondary hypofunction: Absence of stimulation by trophic hormones (ex. pituitary)
    • 3. Other causes: Lack of enzymes, or defects in target organ. (ex. nutritional imbalance)
  6. The Pituitary Gland
    "The Master Gland"
  7. Pituitary Adenoma
    almost all cases of hypersecretion of anterior pituitary hormones are due to pituitary adenomas
  8. Posterior Pituitary Hormones
    • ADH: Stimulates uptake of H2O in the kidney
    • deficiency: diabetes insipidus- excessive urination leads to an increased thirst. If unchecked, can lead to electrolyte imbalance
    • excess: reabsorb too much H2O, leads to edema
  9. Hyperthyroidism: Thyrotoxicosis
    • caused by increased levels of free T3 and T4 hormones
    • Graves' disease: is the cause of 95% of all cases
  10. Thyrotoxicosis Clinical Manifestations (signs/symptoms)
    nervousness, anxiety, weight loss in spite of good appetite, increased BMR (basal metabolic rate), heat intolerance, increased sweating, infertility, palpitations, tachycardia, insomnia, fine tremors, muscle weakness, and goiter
  11. Hypothyroidism: Cretinism
    • happens when fetus doesn't get enough Iodine
    • a maternal deficiency during pregnancy leads to a failure of the thyroid gland
    • interferes with brain development
  12. Cretinism Clinical Manifestations (signs/symptoms)
    retardation of mental faculties, short stature, and protruding tongue
  13. Hypothyroidism: Myexdema
    • Iodine deficiency in adults & older children
    • Clinical Manifestations (signs/symptoms): general apathy, mental sluggishness, cold intolerance, often obese and decreased bowel activity
  14. Hypothyroidism: Graves' Disease
    • Autoimmune disease
    • Clinical manifestations: Thyrotoxicosis (most common cause): increased volume of connective tissue accumulates behind the eye, common disease affecting females 7x more often than males
  15. Hypothyroidism: Hashimoto Thyroiditis
    • most common cause of hypothyroidism
    • cells or thyroid gland are destroyed
    • etiology: autoimmune inflammatory disease
    • clinical manifestations: painless enlargement of thyroid
    • females 10x > males
  16. Hyperparathyroidism - Excess PTH Secretion
    • Parathyroid adenoma: tumor
    • Parathyroid hyperplasia: overgrowth
    • Renal disease: kidney disease
  17. Hyperparathyroidism - Excess PTH Secretion Clincial manifestations
    • decreased serum phosphate
    • lethargy, convulsions, coma
    • failure of water absorption in the nepron, kidney stones
    • peptic ulcers, cardiac arrhythmias, and metastatic calcification
  18. Hyperparathyroidis - Decreased PTH Secretion
    • Iatrogenic, accidental removal and congenital absence
    • Clinical manifestations: neuromuscular irritability, perioral numbness, and decreased sensation of hands and feet
  19. The Adrenal Cortex: Cushing's Syndrome
    • Adrenal Coritcal Adenoma: Tumor
    • Clinical manifestations: too much coritsol causes redistribution of body fat from extremities to the trunk, moon face, elevated cholesterol, diabetes mellitus, increased protein catabolism, sodium retention at the expense of potassium, euphoria, mania, psychosis, decreased resistance to infection, acne, and hirsutism
  20. Hyperparathyroidis: Conn's syndrome
    • Adenoma: tumor
    • clinical manifestations: hypertension, sodium and water retention, and hypokalemia
  21. Decreased secretion: Addison's Disease
    • Rare
    • affects 13,000 in U.S.
    • often between 30-50 yrs
    • clinical manifestations: hypotension (low blood pressure), hyperpigmented skin, hypoatremia (low sodium), hypochloremia (low chloride) and hypoglycema (low sugar)
  22. Diabetes mellitus
    Chronic metabolic disorder secondary to the body's decreased secretion (type I) or sensitivity to insulin (type II)
  23. Diabetes mellitus: Type I (Insulin dependent)
    • Begins early in life
    • failure of insulin synthesis
    • usually onset before 30 yrs
    • problem with cells
    • without insulin the sugar can't enter the cells
    • clinical manifestations: polyuria (lots of urine), polydispsia (thirst), weight loss despite increased appetite
    • emergency complications: shock, death (6th leading cause, 224,000)
  24. Diabetes mellitus: Type II (non-insulin dependent)
    • beings later in life
    • most common form
    • strong association with obesity
    • charcterized by normal plasma insulin concentration with increased blood sugar concentration
    • failure of insulin sensitivity
    • adipose tissues produced the hormone resistin that resists effects of insulin
    • clinical manifestations: polyuria, polydispsia, nocturia (urine at night). Long term complications: poor blood sugar control (hyperglycemia). Coronary artery disease, myocardial infarction, atherosclerosis, peripheral vascular disease (limb ischemia), peripheral neuropathy, blindness, and fatty liver.
  25. Hypoglycemia
    • low blood sugar
    • a diminished concentration of glucose in the blood
    • happens faster than normal
    • clinical manifestations: tremors, cold sweats, and headache. Results from an imbalance or hepatic production and utilization of glucose
Card Set
Path 2: Endocrine System
Path 2: Endocrine System for Quiz/Final