Baroreceptors and Blood Pressure Flashcards
flow, pressure, resistance relationship
flow = delta pressure / resistance
how is arterial blood pressure calculated
arterial blood pressure = cardiac output x total peripheral resistance
what does it mean that blood pressure is pulsitile
diastolic and systolic pressure varies
how is blood pressure controlled short term and long term
short term - baroreceptor reflex (neural control)
long term - RAAS system (hormonal control)
describe the baroreceptor reflex feedback loop
stretch sensitive baroreceptors act as sensors (afferents)
cardiovascular control centre in medulla oblongata acts as integrator
autonomic neurons act as the effectors (efferents)
where are arterial baroreceptors located and why is their location ideal
carotid sinus - measures bp to head
aortic arch - measures bp out the heart
where are cardiopulmonary baroreceptors located
heart
pulmonary artery
what is the process of baroreceptor activation - fall in bp
increase of bp activates stretch receptors
afferent signals (glossopharyngeal nerve)
impulses transmitted to NTS
inhibition of SNS
reduction in smooth muscle contraction
vasodilation
fall in bp
what are the functions of A-fibres and C-fibres
where are they
A-fibres respond to blood pressure changes within the normal range, aortic arch
C-fibres respond to high level blood pressure changes, carotid
chronotropy
heart rate
Dromotropy
conduction velocity within the heart
inotropy
muscle contraction force of the heart
Lusitropy
time taken to relax
how is long term blood pressure primarily controlled
volume control
how is plasma volume altered
salt excretion by RAAS
antidiuretic hormone
atrial natriuretic peptide
