Flashcards in CAM201: Blood Pressure Haemostasis Deck (3)
What systems are involved in short and long term regulation of blood pressure?
Short term: Baroreflex
Long Term: Renin-Angiotensin-Aldosterone System
Describe how the baroreflex works
Stretch receptors are located in the coronary sinuses and (most notable) the aortic arch.
They respond to increased or decreased stretch.
For example, with increased BP there is increased stretched, and thus there is an increased frequency in effect signals to the Cardiovascular centre in the medulla oblongata.
Increased efferent signals from baroreceptors results in increased PSNS activity and suppression of SNS activity on the heart muscles: release of acetylcholine onto anredergic receptors on cells in SA and AV nodes. This results in a negative inopropic and negative chronotropic effeect.
Decreased efferent signals from baroreceptors results increased SNS activity and suppresses PSNS activity. Result is NA/A being released onto beta receptors in heart, increasing contractility and HR.