Endocrine Flashcards
Hypothalamus
Part of diencephalon that connects to pituitary gland through the infundibular or pituitary stalk. Regulates ANS (body temp, appetite, sweating, thirst, sexual behavior, rage, fear, blood pressure, sleep) and other endocrine glands through impact on pituitary gland.
Pituitary gland
Releases hormones that regulate several other endocrine glands. Influenced by seasonal changes or emotional stress. Secretes endorphins and reduces sensitivity to pain. Controls ovulation and production of sex hormones.
Thyroid gland
Controls rate at which cells burn the fuel from food. Increase in thyroid hormones will increase the rate of chemical reactions within body.
Parathyroid glands
Maintains normal blood levels of calcium and phosphate. Parathyroid hormone increases reabsorption of calcium and phosphate from bones to blood. Clotting, neuromuscular excitability, and cell membrane permeability are dependent on normal calcium levels.
Adrenal glands
Located on top of each kidney. Adrenal cortex produces corticosteroids that regulate water and sodium balance, response to stress, immune system, sexual development and function, and metabolism. Adrenal medulla produces epinepherine that increases heart rate and blood pressure with increased stress.
Pancreas
In upper left quadrant of abdomen. Produces glucagon and insulin. Ensure consistent level of glucose in blood stream and maintain stores of energy in body.
Ovaries
Secretes estrogen and progesterone.
Testes
Secretes androgens (testosterone)
Steroid hormones
E.g. prostaglandins
Do not circulate in blood and only exert effects where produced.
Related to inflammation, pain mechanisms, vasodilation, vasoconstriction, nutrient metabolism, and blood clotting.
Amine hormones
E.g. catecholamines (epinephrine, norepinephrine, and dopamine).
Produced in adrenal medulla. Sympathetic nervous system stimulation releases the catecholamines into the blood stream, playing a role in flight or fight response. Increases cardiac contraction, constricts blood vessels, activates glycogen breakdown, blocks insulin secretion, increases metabolic rate, and dilates airways within lungs.
Peptide hormones
E.g. insulin
Insulin released when there is elevation in the level of blood glucose, increasing uptake of glucose for metabolism.
Hypopituitarism
Rare disorders with symptoms that may include dwarfism, delayed growth and puberty, sexual and reproductive disorders, and diabetes insipidus.
Orthostatic hypotension. Bilateral hemianopsia.
Hyperpituitarism
Symptoms include gigantism or acromegaly, galactorrhea (abnormal lactation in males or females), amenorrhea, infertility, and impotence.
Bilateral carpal tunnel syndrome, arthritis, osteophyte formation
Addison’s Disease
Hypofunction of adrenal cortex.
Etiology: Decreased production of cortisol and aldosterone.
Signs/symptoms: Hypotension, weakness, anorexia, weight loss, altered pigmentation, if untreated shock and death.
Treatment: Corticosteroids and mineralcorticoids
Cushing’s Syndrome
Hyperfunction of adrenal gland.
Etiology: Excessive cortisol production.
Sings/symptoms: Hyperglycemia, growth failure, truncal obesity, purple abdominal striae, moon shaped face, buffalo hump, weakness, acne, hypertension, depression, poor concentration, and memory loss.
Hypothyroidism
Slows metabolic processes. Symptoms include fatigue, weakness, decreased HR, weight gain, constipation, delayed puberty, and retarded growth/development.
Hyperthyroidism
Symptoms include increase in nervousness, excessive sweating, weight loss, increase in BP, exophthalmos, myopathy, chronic periarthritis, and enlarged thyroid gland.
Grave’s disease
Most specific cause of hyperthyroidism. Most common in women over age 20.
Etiology: Autoimmune disease in which antibodies produced by immune system overstimulate thyroid gland.
Signs/symptoms: enlarged thyroid gland, heat intolerance, nervousness, weight loss, tremor, and palpitations.
Treatment: Pharmacological intervention and/or removal of thyroid glad using radiation or surgery.
Hypoparathyroidism
Symptoms include hypocalcemia, neurological symptoms like seizures, cognitive defects, short stature, tetany, muscle pain, and cramps.
Treatment includes rapid elevation in serum calcium levels through IV. Long term treatment includes pharmacological management and dietary modifications.
Hyperparathyroidism
Symptoms include renal stones and kidney damage, depression, memory loss, muscle wasting, bone deformity, and myopathy.
Acute treatment includes pharmacological intervention that lowers serum calcium using diuretics or antiresorptive meds. Surgical intervention required to remove disease parathyroid gland.
Type I Diabetes Mellitus
Pancreas fails to produce enough or any insulin. Normally diagnosed in childhood but can occur at any age. Known as insulin-dependent or juvenile diabetes.
Etiology: Genetic predisposition in combination with viral or environmental trigger may cause immune response that damages pancreas.
Signs/symptoms: Rapid onset of symptoms, polyphagia, weight loss, ketoacidosis, polyuria, polydipsia, blurred vision, dehydration, and fatigue.
Treatment: Insulin injections, exercise, and nutritional management.
Type II Diabetes Mellitus
Usually occurs over the age of 45 but can occur in children. Usually can produce some insulin but resistant to insulin receptor sites.
Etiology: Hyperglycemia, obesity.
Signs/symptoms: Same as type 1 DM but ketoacidosis does not occur. Gradual onset.
Treatment: Blood glucose control through diet, exercise, oral medication, or insulin injections.
Gestational Diabetes
Increase in insulin resistance during pregnancy, usually in last trimester. Believed that hormones that assist the fetus to grow may lead to insulin resistance. Usually return to normal glucose metabolism after pregnancy. Babies at risk for increase glucose levels and increased size. Baby may have breathing difficulties, jaundice, and hypoglycemia after birth.
Diabetes Testing
Fasting plasma glucose: > 125 mg/dL is positive
Oral glucose tolerance test: blood glucose test 2 hours after sugary drink. > 200 mg/dL is positive
A1c testing: based on attachment of glucose to hemoglobin over past 2-3 months. > 6.5% is positive
