Arterial Pressure Reg Flashcards
Regulation of _______ ________ is accomplished by a complex system of positive and negative feedback systems.
arterial pressure
arterial pressure maintained by multiple ______ and ______ systems
nervous and hormonal
mean arterial pressure needed to allow for adequate _______ ______ to all tissues
nutrient delivery
At critical flows blood shunted to critical systems for life: ______ _______ _______
CNS, heart, kidneys
At basic level, Regulation of arterial pressure determined by ___________ __________ and _____ ________ ________
Cardiac Output CO-
Total Peripheral Resistance TPR
mechanoreceptors for transducing pressure and pressure changes to NS AP —> CNS (nervous portion)
baroreceptors
baroreceptor locations (2)
carotid sinus-
aortic arch
Baroreceptors sensitive to (2)
changes in pressure-
rate of change of pressure
baroreceptor impulses carried via CNs ___ and ___ to the _____ and ______
IX glosopharangeal and X Begus=
medulla and pons
Medulla/ pons regulation of BP via the ______ _____ ______ modulating _______/__________ NS outflow to _____ and _______ ________
autonomic nervous system -
sympathetic/parasympathetic-
heart and blood vessels
level of contractility ^ or v by
the level of sympathetic “tone” to arterioles and venules (vascular smooth muscle)
CNS CHEMORECEPTORS react to levels of ___, ____, and _____ in blood and CSF
O2, CO2, and pH
stimulation of CNS chemoreceptors results in symp or parasymp modification of ____ ______
blood pressure
disorders that may lead to autonomic hyperreflexia
higher spinal cord injury, MS
intracerebral bleed may lead to
acute hypertension
afferent neuron disease or peripheral neuropathies may be from
diabetes mellitus, alcoholic neurophathy, tabes dorsalis
angiotensenogen released systemically by
liver–in response to decreased BP or adverse Na concentrations
Renin released by _____ and cleaves angiotensenogen to form__________
kidneys-
angiotensin I
ACE
angiotensin converting enzyme–pulmonary circulation
ACE further modifies ___________ to form ___________
angiotensen I, angiotensen II
ACE also produced in vasculature of ______, _______, ______, and _______
adrenal gland, heart, brain, kidneys
2 main systems for arterial pressure drug regulation
- autonomic NS
- Renin-angiotensin-aldosterone system
Nervous/hormone
faster system for arterial pressure regulation
Nervous over hormonal
^ vagal tone =
slow heart contractility
dx of nerve damage as from diabetes for orthostatic hypotension
- take BP/pulse just after standing
dx of orthostatic for autonomic dysfunction
take serial BP 10 min after standing
Nervous control of arterial pressure constituents 3.
- baroreceptors (carotid sinus & aortic arch)
- baroreceptor reflex sequence (CN IX & X) study ppt slide 6
- chemoreceptors (central & peripheral–O2, CO2, & pH)
no O2 in environment –> minute ventilation will go
way up–usually driven by CaCO2
Angiotensen II primarly leads to release of _______ from adrenal cortex (zona glomerulosa cells)
aldosterone
aldosterone acts on ______ ______ ______ cells promoting INCREASED reabsorption of ____, ^ blood volume
distal renal tubule,
sodium Na+
angiotensin II further actions 3
- acts as direct vasoconstrictor–> ^total peripheral resistance
- constriction of renal efferent arterioles (preserve GFR)
- stimulates Na+ - H+ exchange in renal proximal tubule ^ Na+/ HCO3 reabsorption
in normal situations of depletion (hemorrhage, dehydration) of circulating blood volume, RAA system
attempts to preserve blood volume and flow
ACE inhibitors will
control hypertension–not as much aldo released
spironolactone
antimineralocorticoid (treats ^ BP)
ADH secreted by
POSTERIOR pituitary–controlled by hypothalamus
ADH secreted in response to
serum osmolarity (norm 295) & low circulating blood volume
ADH promotes– V1 receptors
renal water reabsorption
ADH promotes–V2 receptors
vasoconstriction in arterioles smooth muscles
Brain natriuretic peptide aka
atrial natriuretic peptide (ANP)
ANP released secreted by ATRIA in response to
increased VOLUME and PRESSURE in atria
ANP inhibits
renal Na+ REABSORPTION & aldo release
ANP useful lab measurement for
heart failure–
ANP opposes
aldosterone – in reference to renal retention of Na+
ANP mediates vasodilation of ________ renal arterioles, and constriction of ______ renal arteriles
AFFERENT,
EFFERENT
Increases GFR
vasopressin also has ________-_______ properties
vaso-contrictive–INCREASES arterial pressure from 2 dirrections slide14
SI ADH
syndrome of inappropriate of ADH – low serum Na+ CONCENTRATION due to high water (blood volume) retention