Physiological Stress Flashcards
what is stress
something that challenges the body’s normal ability to maintain homeostasis
what centre of brain monitors stress
hypothalmus
what is the short -term response to stress
adrenal medulla= release of catecholamines: adrenaline and noradrenaline
sympathetic NS= releases noradrenaline
what is the long-term response to stress
adrenal cortex= release of cortisol
what is the effect of noradrenaline being released by the sympathetic NS
- vasoconstriction= higher bp
- increase ventilation
- increase sweating
- increase HR/SV= increase CO
- increase blood to brain/heart/skeletal muscle
what is the effect of adrenaline release from the adrenal medulla
mobilisation of FA gluco-neogenesis glyco-geno-lysis vasodilation (alpha 1 receptor) inhibit insulin stimulate glucagon
what is the effect of noradrenaline release from the adrenal medulla
vasoconstriction
high BP
stimulate glucagon
inhibit insulin
condition whereby tumour in adrenal medulla is called…
phaechromocytoma (amplified affects of hormones)
treatment= surgically remove
what is the effect of cortisol release
increase blood glucose (gluconeogensis, vasoconstriction = high bp increase HR increase FA mobilisation protein catabolism ANTI-INFLAMMATION RESPONSE (used as anti-inflammatory drug to prevent autoimmune disease)
when is the release of cortisol higest
morning- triggered by daylight
cortisol release is dependant on 2 releasing hormones. what are they
ACTH- pituitary gland
CRH- hypothalamus
condition when too much cortisol secreted
cushing’s disease= hyperglycaemia, moon- face, buffalo hump, thin limbs, high BP
remove tumour to treat
condition when not enough cortisol
addinsons disease= caused by an autoimmune condition
replace cortisol via aldosterone to treat
