L2 - Adrenal glands/adrenal gland dysfunction/Exogenous Steroid Flashcards
2 parts of adrenal gland
cortex and medulla
where are adrenaline and noradrenaline produced in the adrenal gland?
medulla
which NS is the medulla part of?
sympathetic
3 layers of cortex?
Zona
Glomerulosa
Fascicula
Reticularis
which hormones are produced in cortex?
corticosteriods
3 types of hormones produced in cortex - according to layers?
G = salt = mineralcorticoid; aldosterone F = sugar = glucocorticoid; cortisol R = sex = gonadocorticoids; adrenal sex hormones
what type of hormone is aldosterone? why?
anti-duiretic - increased Na+ reabsorption, therefore water reabs. and increased in K+ output
what causes the release of all the hormones from the adrenal gland?
- hypothalamus
- anterior pituary releases ACTH (adreno-cortico tropic hormone)
- stimulates adrenal gland to release hormones
4 adrenal gland dysfunctions
- addisons disease
- cushings syndrome
- hyperaldostronism (Conn’s syndrome)
- androgenital syndrome
what is hyperaldosteronism?
excess aldosterone - increased Na+ causing hypertension and low K+ levels
what is androgenital syndrome?
excess production of gonadocorticoids
what are the sxs of androgenital syndrome
female hirsutism = facial hair
male psuedohermaphroditism in female infants
precocious puberty = reaching puberty earlier
cause of androgenital syndrome
defect in an enzyme in corticol steriodogenic pathway
what is addisons disease?
lack of aldosterone and cortisol production
addisons disease sxs
- chronic fatigue
- muscle weakness
- decrease appetite and weight
- skin hyperpigmentation
which 2 drugs are treatment for addisons?
fludrocortison - to replace aldosterone
hydrocortisone - to replace loss of cortisol
what is cushings syndrome?
excess glucocorticoid hormone production
ACTH stimulates the adrenal cortex to release what?
corticosteriods
what area of the adrenal gland prodcues aldosterone?
cortex
Damage to cells of the zona fasciculata of the adrenal cortex would result in
a) the loss of axillary and pubic hair.
b) increased volume of urine formation.
c) decreased levels of sodium ion in the blood.
d) decreased ability to convert amino acids to glucose.
d - main effects of cortisol is to promote gluconeogenesis
A rise in cortisol would cause an increase in each of the following, EXCEPT
a) the rate of glucose synthesis by the liver.
b) the level of fatty acids in the blood.
c) fatty acid metabolism by muscle cells.
d) corticotrophin levels.
d
syndrome which is a cause of secondary hypertension
conn’s syndrome
sxs and symptoms of this disease are moon face, osteoporosis, central body obesity, glucose intolerance
cushings disease
drug which is also called hydrocortisone
cortisol
glucocorticoid which is a prodrug with a short duration of action
deflazacort
most common glucocorticoid drug used as anti-inflammatory and immunusupression
prednisolone
drug used in addisons disease in conjuction with cortisol
fludocortisone
2 times in the day where cortisol secretion peaks
- early morning
2. noon
3 mechanisms which control release of aldosterone?
- stress
- decreased Na+ and increased K+ in blood
- decreased BP/blood volume
how does stress cause release of aldosterone ?
- hypothalamus detects
- releases corticotropin releasing hormone (CRH)
- ant pit releases ACTH
how does decreased Na+ and increased K+ in blood cause release of aldosterone?
direct effect
how does decreased BP/blood volume cause release of aldosterone?
- detetced by kidney
- kidney releases renin
- cascade produces angiotensin II
what hormone works to decrease BP etc?
ANP
4 general functions of glucocorticoids?
- metabolic
- permissive
- adaptation to stress
- anti-inflammatory/immunosuppresive
3 metabolic effects of cortisol?
- hyperglycaemia
- protein degradation
- lipolysis
describe 1 permissive effect of cortisol on other hormones?
allows catecholamines (NE/E) to induce vasoconstriction
in terms of the cortisol short term adaptation to stress - what effects does it have?
causes adrenal medulla to secrete Ne E
in terms of the cortisol long term adaptation to stress - what effects does it have?
same as mineralcorticoid - CRH from hypothalamus etc
list 5 ways in which cortisol acts as an anti-inflammatory/immunosuppresive
- reduce vasodilation and dec fluid exudation
- dec number + activity of WBC
- dec fibrosis
- dec action/proliferation of lymphocytes
- dec production of prostanoids/leukotrienes
- dec generation of cytokines
- dec complement protiens
- dec histamine release from mast cells
what 2 things can excess glucocorticoid levels lead to?
- depress bone + cartilage formation
2. promote changes in CV, neural and GI function
what does the renin-angiotensin system promote the release of?
mineralcorticoids and glucocorticoids
when are cortisol levels the highest
morning
what is conn’s syndrome ?
hypoaldosteronism
sxs of conns syndrome
hypertension - low K+
list 5 sxs of cushings syndrome
- moon face
- central body obesity
- thin, bruised skin
- glucose intolerance
- hypertension
- excess hair growth
- osteoporosis
- kidney stones
- menstrual irregularity
- emotional liability
- increased susceptability to infections
2 treatments of cushing sundrome
- surgically remove tumour
2. drugs to inhibit cortisol production
3 drugs which inhibit cortisol production
- metyrapone
- trilostane
- aminogluethimide
common use of steriod drugs
anti-inflammatory/immunosuppressive
why can cortisone and prednisone only be admisteretd systemically
they convert into active form by the liver
name 1 short acting corticoid
hydrocortisone
name 1 intermediate acting corticoid
predisone
name 1 long acting corticoid
betamethasone
3 side effects of large doses and long term effects of corticosteroids
- iatrogenic cushing syndrome
- infection/injury suppression - chicken pox
- hypothalamic-pit-adrenal suppresion - prevents natural steriods from being produced
when can glucocorticoids be abruptly discontinued?
if low dose
<3 weeks
3 sxs of glucocorticoids withdrawal
- fatigue
- muscle weakness
- arthralgia
- nausea
- hypotension
- dizziness
