Chapter 20.2, Problem 19AYLO

Summary Introduction

To discuss:

How vasomotion can change system-wide blood pressure or redirect blood flow from one region to another; circumstances that call for redirection of the blood flow.

Introduction:

The vasoconstriction and vasodilation are collectively called as vasomotion. The narrowing of the vessel is called as vasoconstriction, and it occurs by contraction of smooth muscle in the tunica media. The widening of the vessel in vasodilation is by muscular passivity rather than muscular effort. The smooth muscles get relaxed, and the blood pressure allows the vessel to expand. The vasomotor center of the brain controls the vasomotion.