Regulation Of Arterial Pressure Flashcards
What N. Correspond to the Carotid sinus baroreceptor
Glossopharyngeal N. (CN IX)
Sinus N of Hering
What N.’s correspond to the Ao. Sinus Baroreceptor
Vagus N. (CN X)
Aortic N.
The afferent pathways of the baroreceptor reflex go to where in the brain and what neruoxmitter do they use here
The nucleus tractus solitarius (NTS)
glutamate as neuroxmitter
What do baroreceptors sense
Change sin pressure through stretch receptors on vessel walls
Increased stretch (increased MAP) will cause what in the baroreceptors
What about decreased stretch
Increased firing of parasympathetic N.S. (Need to chill out with amount of blood)
Decreased firing of parasympathetic N.S with pressure and stretch decrease, and sympathetic N.S takes over
The baroreceptors are most responsive to what
The rate of change in pressure
Increased stretch and thus increased pressure causes what in terms of paraympathetic and sympathetic N.S.
Increased stretch means increased MAP and thus increased paraympathetic N.S. And decreased sympathetic N.S.
The parasympathetic efferent response travels through what in the brain
The dorsal motor nucleus of the vagus and the nucleus ambiguus
The sympathetic efferent signal travels through what in the brain
Rostral ventrolateral medulla
SV is dependent on what
Sympathetic stimulation
Preload
HR is dependent on what
Symp and Parasymp Stimulation
Increased frequency of stimulation does what in terms of parasympathetic firing and what does this mean physiologically
Increases strength of AP
Fires until about 200 mmHg, then levels out
The aortic sinus has a what compared to the carotid sinus and is less sensitive to what
Higher threshold for activation and less sensitive to rate or decrease in AP
What receptor increases Hr and contractility
What about constriction of arterioles and veins
B1
A
What N effects the SA node paraympathetically and with what receptor
Vagus N to SA Node with mAChr
How does HTN effect baroreceptors
Resets them to a higher set point
What does the RAAS control in general terms
Long-term regulation of blood volume
Renin is stimulated by what receptors
B1
Renin is secreted from what
Juxtaglomerular (JG) cells in the kidneys in response to low BP and sympathetic stim.
What does Angiotensin II bind to in arterioles to cause vasoconstriction and what does this mean physiologically
AT1 receptors which increases TPR and BP
What receptors does vasopressin act on
V1 (SM) and V2(collecting ducts) to increase TPR and water retention
What does ANPs do and when is it secreted
Secreted during excessive preload of atria and vent.
Causes arteriolar dilation - decreased TRP
Increased fluid loss - decreases preload
Inhibits renin
A decrease in VR, preload, SV, Co and MAP will do what to the vascular function curve
Shift it L (decreased pressure in LV)
What receptors in the atria sense changes in blood volume
What about the ventricles
A fibers
B fibers
What receptor is acted on during exercise and what happens physiologically
B1
Increased symp., decreased parasymp.
Increased HR/inotropy
Increased VR
Slight increase in MAP
Vasopressin is secreted in response to what and what does it do
ANG II, low preload
Increases TPR and water retention
