endocrine Flashcards
the endocrine system (what, includes (7)
works with the nervous system to control overall body function and regulation, including:
- metabolism
- nutrition
- elimination
- temperature
- fluid/electrolyte balance
- growth
- reproduction
tip:
- secretes hormones and substances into blood sugar from endocrine gland
- secrete substances to abductal system (epithelial surfaces) to salivary glands
disorders of the endocrine system are usually related to: (3)
- excess of a specific hormone (hyper)
- excess of a deficiency hormone (hypo)
- a receptor defect
tip:
- hypothalamus: corticotropin releasing hormone (CRH), thyrotropin-releasing hormone (TRH), gonadotropin-releasing hormone (GnHR), growth hormone releasing hormone (GHRH), growth hormone inhibiting hormone (somatostatin GHIH), prolactin-inhibiting hormone (PIH), melanocyte-inhibiting hormone (MIH)
- anterior pituitary: thyroid stimulating hormone (TSH), adrenocorticotropic hormone (ACTH), luteinizing hormone (LH), follicle-stimulating hormone (FSH), prolactin (PRL), growth hormone (GH), melanocyte stimulating hormone (MSH)
- posterior pituitary: vasopressin (ADH), oxytocin
- thyroid: T3, T4, calcitonin
- parathyroid: parathyroid hormone (PTH)
- adrenal cortex: glucocorticoids (cortisol), mineralcorticoids (aldosterone)
- ovary: estrogen, progesterone
- tests: testosterone
- pancreas: insulin, glucagon, somatostatin
the endocrine system uses the negative feedback loop concept: (4)
- hormone secretion usually depends on the body’s need for the final action of that hormone
- when a body condition starts to move away from the normal range, secretion of the hormone capable of starting the correcting action is stimulated until the need (demand) is met, and the body returns to normal
- as the correction occurs, hormone secretion decreases (may halt)
- control of hormone synthesis is “negative feedback” d/t the hormone causes opposite action of the initial condition change
tip:
- hormone increased concentration -> body will work to inhibit (decrease) levels
- hormone decreased concentration -> body will work to stimulate (increase) levels
- KEY: inverse relationship
functions of the thyroid hormones (8)
- control metabolic rate of all cells (increase O2)
- promote sufficient pituitary secretion of growth hormone and gonadotropins
- regulate protein, carbohydrate, and fat metabolism
- exert effects on heart rate and contractility
- increase RBC production
- affect respiratory rate and drive
- increase bone formation and decrease bone resorption of calcium (T3/T4/calcitonin)
- act as insulin antagonists
tip:
- PTH affects calcium
functions of the parathyroid hormone (4)
- regulates calcium and phosphorus metabolism by acting on bones, the kidneys, and the GI tract
- PTH INCREASES bone resorption (bone release of calcium -> blood from bone storage sites), this INCREASING serum CA
- PTH activates vitamin D, which then increases absorption of calcium and phosphorus from the intestines
- in the kidney tubules, PTH allows calcium to be reabsorbed and put back into the blood
functions of the adrenal gland (adrenal cortex (2), adrenal medulla (1))
1) adrenal cortex:
- mineralcorticoids: aldosterone maintains extracellular fluid volume by promoting sodium and water resorption and potassium excretion in the kidney tubules
- glucocorticoids: cortisol affects the body’s response to stress; carbohydrates, protein, and fat metabolism; emotional stability; immune function; H2O/Na balance
2) adrenal medulla:
- catecholamines: epinephrine/norepinephrine; where stress triggers increase secretion of these hormones, resulting in the fight-or-flight response
tip:
- adrenal cortex: androgens (male)
- adernal medulla: Autonomic nervous system, releases catecholamines
endocrine changes associated with aging (4)
- decreased ADH production: urine MORE DILUTE, may not concentrate when fluid intake is LOW
- decreased ovarian production of estrogen: bone density decreases, skin thinner/drier/greater risk for injury, perineal and vaginal tissues become drier and the risk for cystitis increases
- decreased glucose tolerance: weight increases, elevated BG lvls, slow wound healing, frequent yeast infections, polydipsia, polyuria
- decreased general metabolism: loss tolerant of cold, decreases appetite, decreased HR/BP
physical assessment endocrine system (3)
1) inspect:
- observe for prominent forehead/jaw
- round/puffy face
- dull/flat expressions
- hyperpigmentation
- buffalo hump (goiter)
- striae
- hirsutism (excess hair around mouth and chin)
2) palpate:
- palpate thyroid gland/tests
3) auscultate:
- auscultate chest for HR, rhythm
- assess BP
- assess for bruits
diagnostic labs (4)
- blood tests: determine the levels of circulating hormones, the presence of autoantibodies, and the effect of a specific hormone on other substances
- the serum levels of a specific hormone: may provide information to determine the presence of hypofunction/hyperfunction of the endocrine system and site of dysfunction
- radioimmunoassays: radioisotope-labeled antigen tests that are commonly indicated blood tests used to measure the levels of hormones or other substances
- urine tests: used to measure the amount of hormones or the end products of hormones excreted by the kidneys
the anterior pituitary gland (adenohypophysis) (what, which hormones (7), disorders (2))
1) controls growth, metabolic activity, and sexual development through the actions of these hormones:
- GH (growth hormone)
- TSH (thyroid stimulating hormone)
- ACTH (adenocorticotropic hormone)
- FSH (follicle-stimulating hormone)
- LH (luteinizing hormone)
- MSH (melanocyte stimulating hormone)
- PRL (prolactin)
2) disorders of the anterior pituitary gland include:
- hypopituitarism: dwarfism
- hyperpituitarism: gigantism (grow really tall, occurs post growth plate fusion), acromegaly
hypopituitarism (what, 3 subtypes, deficiencies/their reactions (3))
1) deficiency of one or more anterior pituitary hormones
- selective hypopituitarism: when only one hormone is affected
- panhypopituitarism: decreased production of ALL ANTERIOR PIT HORMONES
2) deficiencies and their reactions:
- ACTH/TSH: most life threatening, vital hormones for LIFE
- gonadotropins: changes sexual function in both men and women
- GH: changes tissue growth
tip:
- acth: adenocorticotropic hormone
- tsh: thyroid stimulating hormone
- gh: growth hormone
- one hormone decreases -> all other hormones decreased to a degree
hypopituitarism s/sx GH deficiences (4)
- decreased bone density
- pathologic fractures
- decreased muscle strength
- increased serum cholesterol levels
hypopituitarism s/sx gonadotropin (women (7), men (7))
1) women:
- amenorrhea
- anovulation
- low estrogen lvls
- breast atrophy
- loss of bone density
- decreased axillary/pubic hair
- decreased libido
2) men:
- decreased facial hair
- decreased ejaculation volume
- reduced muscle mass
- loss of bone density
- decreased body hair
- decreased libido
- impotence
hypopituitarism s/sx TSH deficiency (9)
- decreased thyroid hormone levels
- weight gain
- intolerance to cold
- scalp alopecia
- hirsutism
- menstrual abnormalities
- decreased libido
- slowed cognition
- lethargy
hypopituitarism s/sx ACTH deficiency (10)
- decreased serum cortisol levels
- pale
- sallow complexion
- malaise/lethargy
- anorexia
- postural hTN
- headache
- hypoglyemia
- hypoNA
- decreased axillary/pubic hair women
hypopituitarism s/sx ADH deficiency (8)
- DI
- greatly increased urine output
- low urine specific gravity
- hTN
- dehydration
- increased plasma osmolarity
- increased thirst
- output does not decrease when fluid intake decreases (polyuria)
hypopituitarism interventions (1, pharm (5))
- mgmt of the adult w/ hypopituitarism focuses on replacement of deficient hormones w/ lifelong treatment
pharm:
- testosterone parenteral or transdermal
- estrogen/progesterone
- human GH SQ injections
- thyroid replacement - will discuss w/hypothyroidism
- cortisol replacement - will discuss w/ addison’s (NOT ON EXAM)
hyperpituarism ((3))
hormone over secretion that occurs with pituitary tumors or tissue hyperplasia
- tumors occur most often in the anterior pituitary cells that produce GH, PRL, ACTH
- usually only ONE hormone is produced in EXCESS d/t cell types within pituitary gland are individually organized
hyperpituitarism s/sx PRL excess (9)
- HYPOgonadism (loss of secondary sexual characteristics)
- decreased gonadotropin levels
- galactorrhea
- increased body fat
- increased serum prolactin levels
- menstrual changes
- decreased libido
- painful intercouse
- difficulty becoming pregnant
hyperpituitarism s/sx GH excess (10)
acromegaly
- thickened lips
- coarse facial features
- increasing head size
- lower jaw protrusion
- enlarged hands and feed
- joint pain
- barrel shaped chest
- hyperglycemia
- sleep apnea
- enlarged heart, lungs, liver
hyperpituitarism s/sx TSH excess (6)
- elevated plasma TSH and thyroid hormone levels
- weight loss
- tachycardia, dysrhythmias
- heat intolerance
- increased GI motility
- fine tremors