Ch 16 Endocrine System Flashcards
What hormones are secreted by the thyroid gland?
T3, T4, calcitonin
What produces T3 and T4?
follicular cells
What produces calcitonin?
parafollicular cells
What is thyroid deficiency in a fetus called?
cretinism
What is hypothyroidism?
hyposecretion of T4 and T3
What is severe or prolonged adult hypothyroidism called?
myxedema
What does hypothyroidism produce in adults?
- sensitivity to cold/low body temp.
- constipation
- weight gain
- thick/dry skin & puffy eyes
- lethargy/myalgias/hypoactive reflexes
- low heart rate
- mental dullness/ memory impairment/ depression
Hyperthyroidism
hyper metabolic state secondary to increased thyroid hormone levels
Grave’s disease
autoimmune disease with weight loss, nervousness, irregular heart beat, sweating, tremor & exophthalmos(edema behind eyes)
Goiter
enlarged thyroid gland
Calcitonin
secreted by the parafollicular cells in the thyroid gland
What stimulates the release of calcitonin?
high blood calcium levels
Hyperparathyroidism
usually caused by a parathyroid gland tumor
Hypoparathyroidism
usually caused by trauma to parathyroid gland, surgical removal, or autoimmune processes
Aldosterone
- secreted by adrenal cortex
- stimulated by hyperkalemia, hyponatremia, angiotensin II
- targets kidney
Hyperaldosteronism (Conn’s disease)
too much aldosterone secreted, hypokalemia
Hypoaldosteronism (Addison’s disease)
not enough aldosterone secretion, hyperkalemia
Cortisol
-secreted by adrenal cortex
-stimulated by patters of eating and activity, peaks after getting up in morning, stress
targets protein breakdown, gluconeogenesis, lipolysis
Cushing’s Syndrome
-excessive amounts of glucocorticoids
-signs and symptoms:
hyperglycemia, moon face, buffalo hump, easy bruising, poor wound healing
Addison’s Disease
deficient amounts of glucocorticoids & aldosterone
Pheochromocytoma
excessive amounts of catecholamines secreted into blood
- usually cause by a tumor of adrenal medulla
Type I Diabetes Mellitus
inadequate or no insulin secretion - cardinal symptoms polyuria polydipsia polyphagia
Type II Diabetes Mellitus
problem in cell signaling cascade, inadequate/ineffective insulin secretion, decreased numbers/effectiveness of insulin receptors, insufficient/ineffective glucose transporters, too much resistin hormone, OR too much liver output of glucose
