What is the relation between the resistance of a blood vessel and its radius?

What is the relation between the resistance of a blood vessel and its radius?
Relation between the resistance of a blood vessel and its radius is governed according to Poiseuille’s Law. If vessel radius decreases, resistance increases by its 4th power. In systemic vascular tree, most of the resistance is contributed by vessels of diameter in the range of 50 – 200 microns. The tone of these resistance vessels is well regulated by humoral and neural influences. Neurally mediated vasoconstriction is through alpha adrenergic receptors on vascular smooth muscle. Vasodilatation is by muscarinic and beta 2 adrenoceptors.

Source: Cardiophile MD - November 6, 2022 Category: Cardiology Authors: Johnson Francis Tags: General Cardiology Source Type: blogs