Exam 5: Chapters 24 Flashcards
What is the role of the hypothalamus?
the coordinating center and secretes releasing factor that stimulates the pituitary gland.
What is the role of the pituitary gland?
the master gland and secretes a trophic hormone that targets a specific endocrine gland.
What is the role of the target organ/gland?
to secrete an ‘acting’ hormone that acts on the body and causes a physiological effect.
What hormones does the anterior pituitary secrete?
prolactin (breasts), TSH (thyroid), ACTH (adrenal gland), GH (liver and cells), LH, FSH
What is upregulation?
prolonged inadequate hormones -> increased number of receptors on the cells -> increased sensitivity
What is downregulation?
prolonged excessive hormones -> decreased number of receptors on the cells -> decreased sensitivity and gland atrophy
What is a primary endocrine disorder?
a disorder that affects the target organ; lab values for trophic hormone and acting hormone go opposite directions
What is a secondary endocrine disorder?
a disorder affecting the pituitary gland; lab values for trophic hormone and acting hormone go in the same direction
What is a tertiary endocrine disorder?
a disorder involving the hypothalamus
What is the pathophysiology of hypothyroidism?
low levels of T3 and T4
Causes of hypothyroidism
iodine deficit, autoimmune disorder (lymphocytic thyroiditis aka Hashimoto’s), treatment of Graves disease
Sx of hypothyroidism
weight gain, lethargy, fatigue, constipation, cold intolerance, memory deficit, poor attention span, hair loss, brittle nails, cretinism, swelling, hypercarotenemia
What is the severe life-threatening extreme sx of hypothyroidism?
myxedema
What is the pathophysiology of hyperthyroidism?
high levels of T3 and T4
Causes of hyperthyroidism
autoimmune disorder (graves diseases) and thyroiditis
Sx of hyperthyroidism
weight loss, insomnia, anxiety, diarrhea, heat intolerance, exophthalmos and bulging eyes
What is the severe life-threatening extreme sx of hyperthyroidism?
thyrotoxic crisis
What are the functions of T3 and T4?
increase metabolic rate, heat generation, increase GI motility, affects brain function, and cell growth
What is the pathophysiology of hypoadrenalism?
also known as Addison’s disease; low levels of cortisol, aldosterone, and androgens
Causes of hypoadrenalism
autoimmune disease, abrupt discontinuation of prolonged administration of glucocorticoids, destruction of the gland
Sx of hypoadrenalism
hypoglycemia, weak, lethargic, hyperkalemia, hyponatremia, dehydration, low of pubic hair and axillary hair, amenorrhea
What is the pathophysiology of hyperadrenalism?
also known as Cushing’s disease; high levels of cortisol, aldosterone, and androgens
Causes of hyperadrenalism
tumor and administration of glucocorticoids
Sx of hyperadrenalism
hyperglycemia, weight gain, moon face, buffalo hump, poor wound healing, hypokalemia, hypernatremia, fluid retention, male pattern hair growth, amenorrhea
