21 - endocrine disorders

define hormones

cell-to-cell communication molecules

where are hormones made

glands or cells

how are hormones transported

by blood

what is the function of hormones

activates physiological repsonse

hormone down regulation

decrease in number of receptors

hormone up regulation

increase in number of receptors

define hypofunction of endocrine system

inadequate hormone production

etiologies of hypofunction

-congenital defects-destruction of gland-receptor defects-drugs-aging

define hyperfunction of endocrine s\ystem

excessive hormone production

etiologies of hyperfunction

-excessive stimulation-hyperplasia-hormone producing tumor

what tells the pituitary gland what to release into the blood?

hormones from hypothalamus

what tells the specific peripheral glands to produce and secrete their hormones

tropic hormones from pituitary

hypothalamus controls

secretion of pituitary

pituitary attached to hypothalamus by

infundibulum

posterior pituitary is extension of neural tissue. AKA

neurohypophysis

anterior pituitary is true endocrine gland. AKA

adenohypophysis

function of posterior pituitary (neurohypophysis)

stores and releases hormones made by the hypothalamus

what hormones are secreted by posterior pituitary (neurohypophysis)

-oxytocin-antidiuretic hormone

what hormones are secreted by anterior pituitary (adenohypophysis)

-human growth hormone (hGH)-thyroid stimulating hormone (TSH)-prolactin (PRL)-adrenocorticotropic hormone (ACTH)-follicle stimulating hormone (FSH)-luteinizing hormone (LH)

function of human growth hormone (hGH) or AKA somatotropin

stimulates secretion of insulin-like growth factors in the liver that promote growth, protein synthesis

function of thyroid stimulating hormone (TSH) AKA thyrotropin

stimulates synthesis and secretion of thyoid hormones by thyroid

function of prolactin (PRL)

promotes milk secretion by mammary glands

function of adrenocorticotropic hormone (ACTH) AKA corticotropin

stimulates glucocorticoid secretion by adrenal cortex

function of gonadotropin: follicle stimulating hormone (FSH)

-ovaries initiates development of oocytes-testes stimulate sperm production

function of gonadotropin: luteinizing hormone (LH)

-ovaries stimulates ovulation-testes stimulates testosterone production

growth hormone secretion is stimulated by

hypoglycemia, fasting, starvation, and stress

growth hormone is inhibited by

increased glucose levels, free fatty acid release, and obesityand cortisol

juvenile GH deficiency:idiopathic GH deficiency

lacking hypothalamic GHRH

juvenile GH deficiency:pitiutary tumors agenesis of the pituitary

cannot produce GH

juvenile GH deficiency:laron-type dwarfism

hereditary defect in IGF production

growth hormone excess:in childhood

gigantism

growth hormone excess:in adulthood

acromegaly

excessive adrenal secretion:hypercortisolism

cushing syndrome

adrenal cortical insufficiency

addison disease

adrenal androgen disorders

congenital adrenal hyperplasia

what secretes steroid hormones

adrenal cortex

which part of the adrenal cortex secretes catecholamines

adrenal medulla

what part of the adrenal cortex secretes sex hormones

zona reticularis

what part of the adrenal cortex secretes glucocorticoids

zona fasciculata

what part of the adrenal cortex secretes aldosterone

zona glomerulosa

cushings syndrome

condition resulting from chronic exposure to excessive circulating glucocorticoid levels

about 68% of cushing disease cases have etiology of

pituitary adenoma (anterior pituitary tumor)

about 17% of cushing's disease cases have etiology of

functional adrenocortical tumor (more common in women then men)

about 15% of cushing's disease cases have etiology of

ectopic ACTH secretion (lung cancers. more common in men than women)

glucocorticoid treatment

latrogenic

clinical manifestations of cushing's disease

-altered fat metabolism (buffalo hump, moon face)-purple stiae-muscle weakness-osteoporosis-hypogonadism-immune suppression

clinical manifestation of addison's disease

-weakness, lethargy, fatique, anorexia, N&V-hypoglycemia-hyperpigmentation-vitiligo-loss of pubic hair (women)

how to diagnose cushing's disease

dexamethasone suppression test-HDST-LDST-ACTH

treatment for addison's disease

oral replacement therapy with steroids (both mineral corticoids and glucocorticoids activity)

define primary hyperaldosteronism

excessive secretion by adrenal cortex

define secondary hyperaldosteronism

excessive secretion of renin from the JG apparatus of the kidneys

what can be the cause of primary hyperaldosteronism

aldosterone secreting adenoma

what can be the cause of secondary hyperaldosteronism

-renal ischemia-decreased intravascular volume-sodium wasting disorders (chronic renal failure)-renine secreting tumors

problems with hyperaldosteronism

sodium retention and hydrogen/potassium excretion which can cause0hypertension-left ventricular enlargement-alkalosis-hypokalemia

treatment for hyperaldosteronism

-surgery to remove adenoma-aldosterone antagonist

adrenal androgen:

-androstenedione- (DHEA) dehydroepiandrosterone

secretion of androgens do what

mimic cortisol which stimulates ACTH

effects of adrenal androgens

-anabolic-masculinizing-women : lipido and orgasm