Chapter 7: Adrenal Gland/Hormones Flashcards
where are the adrenal glands located
above the kidneys in a capsule of fat
adrenal cortex
outer portion
adrenal medulla
inner portion
what does the adrenal cortex secrete
steroid hormones
EXAMPLE: cortisol, DHEA
what does the adrenal medulla secrete
catecholamine
EXAMPLE: epinephrine and norepinephrine
what are the three divisions of the adrenal cortex
- zona glomerulosa
- zona fasciculata
- zona reticularis
the zona glomerulosa secretes
mineralcorticoids
zona fasciculata secretes
glucocorticoids
zona reticularis secretes
sex steriods
example of mineralcorticoids
- aldosterone
what is the main function of mineral corticoids
- influence mineral balance (specifically NA and K)
example of glucocorticoids
cortisol
what is the main function of glucocorticoids
- major role in glucose, preotien and lipid metabolism
examples of sex hormones
- dehydroepiandrosterone (DHEA)
- estrogen and progesterone
aldosterone is transported through the blood using
albuims
aldosterone effects the _________ and _________ of the kidney
distal and collecting tubule
what are the functions of aldosterone
- promotes sodium retention and enhances k elimination during urine formation
- na retention induces osmotic retention of h2o, expanding the ECF volume and maintaining long term blood pressure
what are the consequences if there is no aldosterone
excessive decrease in plasma volume leading to the death of a person by circulatory shock
aldosterone increases by (3 ways)
- activation of the RAAS due to the reduction in NA and a fall in the blood pressure
- direct stimulation of the adrenal cortex by a rise in the k concencentration
- angiotension promotes the growth of z. glomerulosa
regulation of aldosterone secretion is largely
independent
aldosterone hypersecretion is caused by
- primary hyperaldosteronism or conn’s syndrom
- secondary hyperaldosteronism
primary hyperaldosteronism or conns syndrome
- hypersecretion of aldosterone by adrenal tunor
secondary hyperaldosteronism
- inappropriately high activity of the rennin-angiotension system (RAAS)
symptoms of aldosterone hypersecretion
- hypernatremia and hypokalemia
- hypertension (due to excessive Na and fluid retention)
disorders of aldosterone hyposecretion
- primary adrenocortical insufficency /. addisons disease
- secondary adrenocortical insufficiency
Primary adrenocortical insufficency
- results from under secretion of all layers of the adrenal cortex
- autoimmune destruction of the adrenal cortex by erroneus adrenal cortex attacking antibodies
- deficency in both aldosterone and cortisol
secondary adrenocortical insufficiency
- occurs due to pituitary and hypothalmus abnormalities
- caused by insufficent ACTH secretion
- only cortisol is deficent
- results in a poor responce to stress
hypokalemia
disturbs cardiac rhythms
- k depletion
hyponatremia
- reduces blood volume
- hypotension
cortisol
poor responce to stress
excessiva ATCH secretion MSH causes
hyperpigmentation
functions of glucocorticoids
- carbohydrates, fat and protein metabolism
- “permissive actions” for other hormonal activities
- help people cope with stress
CHO metabolism process
fasting –> liver –> glycogenolysis –> glycogen –> glucose –> blood –> brain
CHO metabolism
- gluconeogenesis
- glucose sparing
- stimulates protein degration in the muscles
- faciliates lipolysis
- pays a role in the adaption of stress
- can have an anti-inflammatory and immunosuppresive effects
- diurnal rhythm
protein metabolism process
cortisol –> gluconeogenesis –> protein –> muscle tissues –> amino acids –> glucose
protein metabolism
- stimulates protein degration; converts muscle proteins into amino acids
- gluconeogensis for repairement of damaged tissue or synthesis of new cellular structures
fat metabolsim process
cortisol –> lipolysis –> fats/lipids –> fatty acids –> glucose (alternate energy sources)
if a person lacking cortisol untreated
patient will enter into circulatory shock in a stressful situation that demands immediate
glucocorticoids suppress
antibody production, prevents allergic reactions, and organ transplant
glucocorticoids are an effective method of treating
rheumatoid arthritis
- inhibits inflammatory responce
prolonged exposure to higher-than- normal concentration of glucocortcoids induces
gastric ulcers, high blood pressure, atherosclerosis, menstral irrregularities and bone thinning
- limited ability to resist infections
Cortisol hypersecretion causes
crushing syndrome
crushing syndrome causes
- overstimulation of adrenal cortex by excessive amounts of CRH and/ or ACTH
- adrenal tumors that uncontrollably secrete cortisol independent of ACTH
- ACTH secreting tumors located in places other than the pituitary gland
crushing syndrome sings and symptoms
- hyperglycaemia glucosuria (adrenal diabetes
- excessive gluconegenesis causes hyperglycemia
- abnormal fat distribution causes “buffalo hump” and “moon face (face oedema)”
what is the only adrenal sex hormone that has biological importance
DHEA
DHEA functions in males
overpowered by testicular testosterone
DHEA function is females
- growth of pubic and axillary hair
- enhance of pubertal growth spurt
- development and maintenance of female sex drive
Adrenogenital syndrome symptoms in adult females
Exerts masculinizing effects
- hirsutism
- deepening of the voice
- breast become smaller and menstruation ceases
Adrenogenital syndrome symptoms in a newborn female
Cause of female hermaphroditism
- have male type genitalia (clitoris looks like male penis)
hirsutism
a female tends to develop a male pattern of body hair
adrenogential syndrome effect in prepubertal males
Precocious pseudo puberty
- premature development of male secondary sexual characteristics
andrenogenital syndrome effects in an adult male
- has no apparent effects
