L20 - Regulation of Arterial pressure and Cardiac Output Flashcards
Where does central comtrol of the heart and blood vessels take place?
the Medullary CVS centre
What kind of outflow goes to the blood vessles and the heart?
Sympathetic
How is mean arterial pressure measured?
Total peripheral pressure x Cardiac output
How is cardiac output measured?
Heart rate x stroke volume
How does the sympathetic nervous system cause Tachycardia?
Sympathetic stimulation activates noradrenaline which acts on the level of the SAN, causing increased firing.
How does the parasympathetic nervous system cause Bradycardia?
Parasympathetic stimulation activates acetylcholine which acts on the level of the SAN
How does the sympathetic nervous system cause vasoconstriction?
a1 receptor activation causes an inctrease in intracellular Ca2+ causing contraction.
What causes vasodilation?
Inhibition of the sympathetic nervous system.
What happens in the baroreceptor reflex?
- inhibition of the SNS or activation of the PNS causes vasodilation decreasing mean artierial pressure and total peripheral pressure.
- Baroreceptors detect an increase in arterial pressure and signal the medulla from afferent pathways.
What do chemoreceptors detect? and where do they send signals?
A decrease in PO2, an increase in PCO2, or an decrease in pH.
Signals are sent to the medulla.
What is the bainbridge
