hormonal regulation #exam4

stimulus of renin

• low BP (detected by granilar cells)

• Or decreased NaCl lvls (detected by macula densa cells)

stimulation by the sympathetic division

renin control center

JG apparatus responds to stimuli and release renin

(needs renin in order to release Ang II)

effectors of Angiotensin II

• vasoconstriction inc. resistance and BP

• kidneys decrease GFR = decrease urine output

• hypothalamus - activation of thirst center (by ang II) to inc. fluid intake and release of ADH (post. pituitary) to decrease urine output

• adrenal cortex - release aldosterone - obligatory water reabsorption

net effect of renin

BV inc. and BP inc.

stimuli that promote release of ADH

Ang II

baroreceptor signaling from heart due to low BV

chemoreceptors in hypothalamus ( inc. blood osmolarity)

ADH control center

hypothalamus detects and sends a signal to post. pituitary to release hormone

ADH effectors

• hypothalamus - activation of thirst center

• kidneys - inc. falcutative water reabsorption = dec. urine output

• blood vessels - casoconstriction

Net effect of ADH

• inc. in BP

• inc. in BV

• dec. in blood osmolarity

Aldosterone stimulus

• Ang II

• dec. Na+ lvls in the blood

• inc. K+ lvls in the blood

Aldosterone control center

adrenal cortex releases into the blood

Aldosterone effectors

• kidney - inc. Na+ reabsorption and obligatory water reabsorption

• kidney - inc. K+ or H+ secretion (regulated by blood pH)

Aldosterone net effect

maintains BV, BP, and Na+ lvls

dec. K+ lvls

Atrial Natriuretic Peptide (ANP) stimulus

inc. stretch of atrial baroreceptors

ANP control center

atria responds to stimuli and releases ANP

ANP effectors

blood vessels - vaso dilation

kidneys - inc. GFR and urine output

kidneys - inc. Na+ secretion and water in urine

kidneys - dec. the release of renin (ang II), aldosterone, and ADH

ANP net effect

dec. in peripheral resistance

dec. in BV

dec. in BP