Zusammenfassung der Ressource
Vascular shunt mechanism
- Definition.
- the redistribution of cardiac output around the body from rest to exercise which increases percentage of blood flow to the skeletal muscles.
- At rest
- high percentage of cardiac output (Q) distributed to organs
- arterioles to the organs vasodilate increasing blood flow while arterioles to the muscles vasoconstrict to limit blood flow
- pre-capillary sphincters dilate, opening up the capillary beds to allow more blood flow to organ cells while constricting closing the capillary beds to the muscle cells
- During exercise
- High percentage of cardiac output (Q) is distributed to skeletal muscles.
- Arterioles and pre-capillarty sphincters serving the capillary beds surround in muscle cells dilate
- This maximises blood flow, nutrient and gaseous exchange
- Arterioles and pre-capillary sphincters vaso-constrict around the organs.