Mechanisms of hormone regulation and endocrine disorders Flashcards
hormones aka chemical messengers
chemical substance secreted by a specific organ or tissue
chemical messengers
- secreted in small but predictable rates
- circulates in the blood
- binds to specific cell receptors
what is a lock and key mechanism
hormones
negative feedback
- hormone secretion depends on the boys need for the final action of that hormone
- body condition starts to move away from the normal range, secretion of hormone is capable starting the correcting action until need is met, and the body condition returns to normal range. As correction occurs, hormone secretion decreases
- hormone causes opposite action of initial condition changes
target cell concept
hormones act only on cells that have receptors specific to that hormone, b/c the shape of the receptor determines which hormone can react with it. < ex lock and key model
hypothalamus (chief gland)
brain region, controls pituitary gland
thyroid gland
affects metabolism among other things
pituitary gland (master gland)
secretes many different hormones , some of which affect other glands
parathyroids
help regulate level of calcium in blood
adrenal glands
trigger fight or flight response
pancreas
regulates level of sugar in the blood
ovary
secretes female sex hormones
testis
secretes male sex hormones
relationship between hypothalamus and pituitary gland is important why
integrates communication between nervous and endocrine systems
where is the hypothalamus located
in the center of the brain
what are the two groups of hormones for hypothalamus
releasing and inhibiting
what is the function of the hormones of the hypothalamus
either simulate or inhibit the secretion of hormones from the pituitary
what are the tropic hormones that control other gland hormone secretion
TSH, ACTH, FSH, an LH
FSH
stimulates secretion of estrogen and development of ova and sperm
LH
stimulates ovulation in female and secretion of sex hormones in male and female
hypersecretion
- gigantism (childhood)
- acromegaly (adulthood) - after epiphyseal closure
- results in hypertrophy of all body organs elevations in blood sugar; lipid levels
hyposecretion
*dwarfism - smaller statue, cognitive delay dependent on type
what are the hormones stored in the posterior pituitary
ADH and oxytocin
antidiuretic hormone (ADH) (vasopressin)
major role is regulation of fluid volume by stimulating reabsorption of water in the renal tubules. ADH is a major vasoconstrictor. Most important stimulates of ADH is plasma osmolarity,
what happens when ADH is released
real tubules reabsorb water, urine is more concentration
what happens when ADH is inhibited
renal tubules do not reabsorb water urine is more dilute
parathyroid glands
secrete parathyroid hormone, raises serum calcium levels, stimulates renal conversion of Vitamin D to its most active form
if serum calcium is low PTH
increases
if serum calcium is high PTH
decreases
what does the adrenal cortex secrete
mineralocorticoids (essential for maintenance of fluid and electrolyte balance), glucocorticoids (effect glucose), most abundant is cortisol
major function of cortisol is
body’s response to stress, carbohydrates, protein, and fat metabolism, emotional stability, immune function, and sodium and water balance
adrenal glands promote reabsorption of
Na and H2O, excretion of K and Hydrogen ions
synthesis and secretion of aldosterone is stimulated by
angiotensin II, hyponatremia and hyperkalemia
endocrine secretes what
glucagon (alpha) and insulin (beta)
glucagon
released from alpha cells in low blood sugar
what does glucagon stimulate
glycogenolysis, gluconeogenesis, and ketogenesis
insulin
regulates metabolism and storage of carbohydrates, fats, and proteins and is released from beta cells in high blood sugar
what does insulin inhibit
gluconeogenesis in liver, facilitates glucose transport into cells, synthesizes protein transports triglycerides in to adipose tissue
DM
chronic hyperglycemia and disturbances in metabolism of carbs, fat, and protein
Type 1 (insulin dependent) - absolute insulin deficiency
- acute vs slow progression >primary beta cell defect
- destruction of islet cells
- abnormal alpha cell function (glucagon)
what are examples of secondary diabetes mellitus
hormonal disease(bushings), drug induced (glucocorticosteroid), and gestational diabetes
name examples of poor control for diabetes
- microvascular vs microvascular
- heart disease and stroke
- HTN
- blindness
- renal dysfunction
- neuropathies
- amputations
what are some acute complications of DM
hypoglycemia, DKA, hyperosmolar hyperglycemic nonketotic syndrome (HHNKS)
what are chronic complications of DM
- microvascular disease - diabetic retinopathy, nephropathy, and neuropathies
- macrovascular disease - cardiovascular disease, stroke, and peripheral vascular disease
- infection
what are the hypoglycemia effects
- primary hypoglycemia
- secondary to insulin/oral ADA
- damage to the CNS - brain can only use glucose for energy and w/out glucose cell death occurs
what are the s/s of hypoglycemia (parasympathetic)
nausea and hunger
what are the s/s of hypoglycemia (CNS)
headache, restlessness, dizziness, yawning, lethargy, drowsiness, paresthesias, inability to carry conversation, confusion, slurred speech, muscle twitching, and coma
hypoglycemia T.I.R.E.D.
T- tachycardia I - irritability R - restless E - excessive hunger D - diaphoresis, depression
blood sugar MNEMONIC
hot and dry - sugar high
cold and clammy - need some candy
what are the nursing implications in diabetes
- obesity is preventable
- know A1C, OGTT, chemistry profile, CBC, and lipid pane;
- know s/s of hypo and hyperglycemia
- know treatment of hypo and hyperglycemia
- teach, monitor, assess, and TEACH
