Endocrine Physiology ML:5 Flashcards
Hypothyroidism
conditions characterized by plasma concentrations of thyroid hormone that are chronically below normal
What are the causes of hypothyroidism
iodine deficiency, thyroid damage, or autoimmune destruction
Symptoms of hypothyroidism
low metabolism, weight gain, cold intolerance, low blood pressure
Hyperthyroidism
conditions characterized by plasma concentrations of thyroid hormone that are chronically above normal
Causes of hyperthyroidism
tumors or autoimmune diseases
Symptoms of hyperthyroidism
high metabolism, weight loss, goiter, increased appetite
Graves disease:
TSI antibodies stimulate the TSH receptor on the thyroid gland
How does a goiter develop
hypo: low T3 and T4
-tells hypothalamus to make TRH, and AP to make TSH and TSH ahs trophic effects on the thyroid gland which causes it to swell
hper: AP is overactive with TSH and TSH causes T3 and T4 and increases thyroid size
Functions of adrenal catecholamines durin stress
mobilizes glucose for energy
mobilizes fatty acids for energy
increased cardiac function
What does zona glomeruloa secrete and regulate
secretes aldosterone and regulates sodium, potassium and blood volume
What does Zona fasciculata secrete?
cortisol
What does zona reticularis secrete?
secrete sex steroids( androgens)
3 clade cascade of stress
-hypothalamus secretes CRH
-Ap secretes ACTH
-adrenal cortex secrets cortisol
Physiological functions of cortisol ( basal or non stress levels)
- metabolic effects: liver glucose production between meals
-permissive of adrenerguc receptors in the cardiovascular system - anti inflammatory/anti immune
-fetal development of brain, intestines, lungs, glands
Functions of cortisol in stress
-catabolizes body stores of nutrients
-bone restoration
-support sympathetic responses related to vasoconstriction
-stimulates erythropoietin: replace RBC’s if bleeding out
-anti-inflammatory/immunosuppression
-inhibtion of non essential functions
Adrenal insufficiency
cortisol hyposecretion
Primary adrenal insufficiency (addison’s disease)
causes
destructive tumors, infections, or autoimmune destruction
Results of primary adrenal insufficiency
hypotension, low blood glucose, high plasma ACTH and high CRH
causes of secondary adrenal insufficiency
AP dysfunction, loss of ACTH
Results of secondary adrenal insufficiency
similar symptoms as in primary adrenal insufficiency but with low plasma ACTH
What is cushings disease
cortisol hypersecretion
What is cushing’s caused by?
hyper secreting tumors of adrenal and AP
Results of cushing’s disease
osteoporosis, thin skin, muscle weakness, high blood glucose
-affects cortisol levels in the blood (hypercortisolism)
disease: ACTH secreting tumor on AP
Aldosterone
increases sodium retention and blood pressure
Vasopressin
increases water retention and blood pressue
Growth hormone
breaks down fast and mobilizes blood glucose
Beta endorphin
pain reliever/mood elevation
Insulin during stress
decreases; with less insulin the levels of glucose, fatty acids and amino acids in the plasma increase
