W10D1P2-Long Term Regulation of Arterial Pressure

only regulate BP in short-term

hinderances of baroreceptor reflexes

they reset their set-point after extended periods at high BP (high MAP becomes the new homeostatic value to be maintained)

why are baroreceptor reflexes only able to regulate BP in the short term

renal and CV systems

long term regulation of blood pressure depends more on blood volume which is regulated by

angiotensin 2, aldosterone, ADH, increase, decrease, decrease, decrease, decrease, decrease, decrease, decrease

Blood volume and long term regulation of arterial pressure example:

1. increase arterial pressure that we want to lower
2. decrease secretion of hormones ___________, __________, ___
3. ________ urine formation and urination by kidneys
4. ________ plasma volume
5. _________ blood volume
6. ________ venous pressure
7. ________ venous return
8. ________ EDV
9. ________ SV
10. ________ CO
11. decrease arterial pressure

decrease arterial O2, increase arterial CO2, decreased brain blood flow, pain in the skin (superficial pain), psychological stress, physical activity, consuming nutrients, weight gain

8 things (independent from baroreceptors) that can increase MAP

deep, bone, or visceral pain (why this may cause fainting), sleeping, happiness

3 things (independent from baroreceptors) that can decrease MAP

peripheral chemoreceptors

O2 and CO2 detection by

located near, but separate from arterial baroreceptors in areas known as aortic bodies and carotid bodies

where are peripheral chemoreceptors

sense decreased O2, increased CO2, decreased pH in artery blood, stimulates VM, increases vasoconstriction which increases TPR and thus MAP

peripheral chemoreceptors: what do they sense and what is their effect

Cushing's phenomenon

usually caused by head trauma
elevated intracranial pressure resulting in large increases in systemic MAP

central chemoreceptors

Cushing's phenomenon is initiated by

central chemoreceptors

located near CA, CI, VM centers
detect CO2 levels in brain ISF

compression, central chemoreceptors, TPR, MAP, worse

clinical consequences of cushing's phenomenon

1. head trauma
2. inward intracranial bleeding and swelling (edema)
3. intracranial pressure build up (increase P of ISF)
4. cerebral artery __________ and thus decrease blood flow to brain
5. build up of local metabolites (increase CO2 in brain ISF)
6. powerful stimulation of ______ ___________
7. increase VM output to arterioles body wide (except brain arterioles) to increase body ___
8. increase in ___ in attempt to increase flow through compressed brain vessels
9. temporary fix to increase pressure and flow to brain, but can actually make swelling _____!