Stress Flashcards
What controls stress?
Hypothalamus
- Nervous system = sympathetic
- Endocrine system
What is short term response to stress?
Sympathetic nervous system
What is Long term response to stress?
Endocrine system
What is the fight or flight short response?
Hypothalamus in CNS > Symp. > Adrenal gland > releases Adrenaline/Noradrenaline
What is central part of adrenal gland?
Adrenal Medulla
What does inner adrenal medulla give?
Brief response
What does outer adrenal cortex give?
Long lasting response
How is rapid response bought about?
granules stored with (nor)adrenaline
What does Adrenaline increase?
glycogenolysis- inc blood glc
gluconeogenesis - inc blood glc
mobilisation of free fatty acids
what does noradrenaline bind to in vasoconstriction
alpha 1 receptor
What does adrenaline bind to in vasodilation ?
Beta 2 receptor in skeletal muscle
how does adrenaline and noradrenaline increase blood glucose?
inhibit insulin and stimulate Glucagon
What is Phaechromocytoma?
benign tumour in adrenal medulla
What happens when adrenal cortex is stimulated?
Cortisol released
How is cortisol released?
Circadian rhythm - continually secreted
What hormones trigger Cortisol release?
Corticotropin- hypothalamus
Adrenocorticotropic hormone- anterior pituitary
What are biological effects of cortisol?
Carb metabolism
Fat metabolism
Protein metabolism
What does Carb metabolism do?
blood glucose increase, inc. gluconeogenesis
decrease glc utilisation
What does fat metabolism do?
inc. fatty acis for energy use instead of Glc
What are the effects of cortisol ?
increase BP- Vasoconstriction
increase HR
Anti inflammatory response - immune response decr. so no autoimmune disease
What are the steps of Cortisol release?
1) stress stimulate Hypothalamus
2) CRH secreted and anterior then releases ACTH
3) ACTH stimulates adrenal cortex to release Cortisol
4) Neg feedback when too much cortisol
What is Cushing Disease? ( Moon face/ buffalo hump)
Hypersecretion of cortisol
tumor in adrenal cortex and anterior pituitary gland
What is Adison’s disease?
Hyposecretion of cortisol
Adrenal cortex and anterior pituitary damaged
What is symptom of adisons disease?
Low BP
hypoglycaemia
