Control Of The Cardiovasular System Flashcards
What are the neural control of the of the vascularture
Symp stim of heart result in brief constrict due to a1-adr recep
Dilation die to b1-adr recep, stim myocardium, and increasing mech and meta act of heart
What innervates the SAN and AVN?
The thoracic parts of the spinal cord (symp) T1-L2
The vagus nerve (para)
What is the definition of inotropic and chronotropic?
Inotropic - force of contraction
Chronotropic: - heart rate
What is the primary affect of b-add activation?
Increases force of contractility and machinery sensitivity
Increases HR
(Symp)
What is the effect of para on the CVS?
Mediated by ACh act musc receptors
Leads to cardiac slowing, inhib AV conduct, -ve ino/chronotropic effect
How are the vessels controlled?
Increasing or decreasing levels of Ca
The SMC contract sensitive to Ca conc
Which adr activates constriction?
A1- adr
Which add activates dilation
B2- adr
Where are the adr/musc receps located?
B1 for AVN
A1 in vessels
M2 in AVN
M3 in vessels
What is the function of the a-adr recep?
A1: Release of Ca leading to contraction of vasc smooth muscle
Vasoconstrict in splanchnic, renal, cut and skeletal musc
A2: also vasoconstrict
What is the function of the b-adr recep?
B1: - increases Ca, +ve ino/chrono and stoke renin release
B2: - activation causes dilation in vessels
What are the cardiac centres in the brain?
The medulla: - accelerator centre and inhibitory centre
Activate symp and parasymp
Receive signals from hypothal, barorecep and chemoreceptors
Nerves which innervate the heart?
Vagus nerve (CN and X) Glossopharyngeal nerve (CN IX) Carotid sinus (barorecep) Carotid body (chemoreceptors) Aortic bodies (chemoreceptors) Aortic arch (baroreceps)
How does pressure affect CV control?
Senses by baroreceps
Increases Pa causes decreased symp act and vice versa
How does volume affect CV control?
Senses by atrial vol recep
Increases vol: - causes decrease in ADH secretion (less water retention)
Increase in atrial natriuretic pep increase urine prod
