Peripheral Circulation And Regulation Of Flow

Question 1

what is the “regulator” for the autonomic system

Answer 1

medulla

Question 2

final central pathway for modulation of sympathetic and parasympathetic drive is in the

Answer 2

medulla

Question 3

baroreceptors are

Answer 3

stretch receptors located on the aortic arch and bifurcation of carotid

Question 4

Parasympathetic pre ganglions are excited by

Answer 4

Increased baroreceptor input

Question 5

B2 receptors in skeletal bed mediates

Answer 5

Vasodilation

Question 6

Arterial chemoreceptors

Answer 6

Located on the aortic arch and bifurcation carotid artery - intermingled with baroreceptor ending
- are most sensitive to blood oxygen levels

Question 7

Other short term cardiovascular reflexes

Answer 7

Cardiopulmonary reflexes
- atrial stretch receptors
-left ventricular receptors
Extrinsic reflex (pain and cold)

Question 8

Atrial stretch receptors “low pressure baroreceptors”

Answer 8

Receptors located in the vent atrial junction
Afferents respond to sudden increasing in blood volume (inspiration, intravenous bolus)
Afferents travel via the vagus nerve to the NTA
Main reflex action is to increase heart rate
- little reflex change in TPR

Question 9

Bainbridge reflex

Answer 9

Atrial volume receptors
 - increase heart rate
 - increased dieresis (water unloading)
Through central pathways modulation of 
 - selection changes in renal blood flow
 - changes in renal capacity for water reabsorption

Question 10

Epinephrine has a higher affinity for

Answer 10

Beta 2 than alpha receptors

Question 11

Norepinephrine has a higher affinity for

Answer 11

Alpha receptors

Question 12

Angiotensin II and vasopressin

Answer 12

Normal circulating levels are low
Released during hypovolemia, dehydration and other disturbances to blood volume/osmolality
Short term vascular effects: potent vasoconstrictors via selective receptors on vasculature, high levels of circulating angiotensin II are associated with many forms of hypertension

Question 13

Angiotensin has __ receptor subtypes: balance of activation

Answer 13

2