13.3 regulation of stress

how is stress response regulated

by hormones of adrenal gland

adrenal glands

on top of each kidney. they have a central adrenal medulla surrounded by the adrenal cortex.

short term stress response (fight or flight)

controlled by hormones of the adrenal medulla epinephrine and norepinephrine. increases bs, br, hr, bp, blood flow to heart and muscles. stress to hypothalamus to adrenal gland by nerves to epinephrine/ norepinephrine

epi pens

used on heart attack patients to start heart. anaphylactic shock used to open air passage

long term stress response (1)

controlled by hormones in adrenal cortex. glucocorticoids increase blood sugar and mineralocorticoids increase blood pressure.

cortisol (2)

glucocorticoid from adrenal cortex. steroid made from cholesterol. raises blood sugar levels. breakdown of muscle and fat. acts as anti inflammatory suppresses immune response

ACTH

released form anterior pituitary, targets adrenal cortex. stimulates release of cortisol. stress to hypothalamus to releasing hormones to anterior pituitary to ACTH to adrenal cortex to cortisol

ACTH 1. negative feedback loop and 2, chronic stress

increased cortisol inhibits release of ACTH from anterior pituitary. sustained high levels of cortisol can be dangerous, impaired thinking, damages heart, high BP, diabetes

aldosterone

main mineralocorticoid. from adrenal cortex and travels to kidney. promotes absorption of NA into blood, result: water flows by osmosis which increases BP and retention of water

aldosterone controls

low BP-> adrenal cortex-> aldosterone-> kidneys-> increase NA and H20 absorption

Addisons disease

not enough mineralocorticoids and glucocorticoids. low BS, NA and K imbalance, weight loss, low BP and increased urine. treated with injections of mineralocorticoids and glucocorticoids