Section 4 Regulation of/the/Circulation
Section 4 Regulation of the Circulation
Introduction The aim: to regulate the blood flow of organs to fit their metabolic requirement in different condition The regulation of blood flow are of three major types Neural Humoral Local
Introduction ➢ The aim: to regulate the blood flow of organs to fit their metabolic requirement in different condition. ➢ The regulation of blood flow are of three major types: ➢ Neural ➢ Humoral ➢ Local
I. NeuralRegulation of the circulation
I. Neural Regulation of the Circulation
1. Innervation of the Circulate System Cardiac innervation Innervation of blood vessels Sympathetic vasoconstrictor fiber Sympathetic vasodilator fiber Parasympathetic nerve fiber to peripheral vessels
1. Innervation of the Circulatory System ➢ Cardiac innervation ➢ Innervation of blood vessels ➢ Sympathetic vasoconstrictor fiber ➢ Sympathetic vasodilator fiber ➢ Parasympathetic nerve fiber to peripheral vessels
Cardiac innervation Sympathetic nerve-noradrenergic / fib er Parasympathetic nerve- cholinergic fiber Noradrenergic sympathetic nerve increase the cardiac rate(positive chronotropic effect Increase the force of cardiac contraction(positive inotropic effect Cholinergic vagal cardiac fibers decrease the heart rate
Cardiac innervation ➢ Sympathetic nerve – noradrenergic fiber ➢ Parasympathetic nerve- cholinergic fiber ➢ Noradrenergic sympathetic nerve ➢ increase the cardiac rate (positive chronotropic effect) ➢ Increase the force of cardiac contraction (positive inotropic effect). ➢ Cholinergic vagal cardiac fibers decrease the heart rate