ANSANS

Prof. Vajira WeerasingheProf. Vajira Weerasinghe

Dept of PhysiologyDept of Physiology

Sympathetic vs Sympathetic vs parasympathetic parasympathetic

►Distribution on different organsDistribution on different organs►Actions on different organsActions on different organs►Drugs acting on receptors Drugs acting on receptors ►Reflexes in different systems Reflexes in different systems

Sympathetic vs Sympathetic vs parasympathetic parasympathetic

►Distribution on different organsDistribution on different organs

Fig. 9.6Fig. 9.6

Sympathetic (Thoracolumbar) Sympathetic (Thoracolumbar) DivisionDivision

► Preganglionic cell bodies in lateral Preganglionic cell bodies in lateral horns of spinal cord T1-L2: horns of spinal cord T1-L2: thoracolumbarthoracolumbar

► Preganglionic axons pass through Preganglionic axons pass through ventral roots to ventral roots to whitewhite rami rami communicantescommunicantes to the to the retroperitoneal retroperitoneal sympathetic chain sympathetic chain gangliaganglia

Parasympathetic Parasympathetic (Craniosacral) Division(Craniosacral) Division

► Preganglionic cell bodies in Preganglionic cell bodies in nuclei of brainstem or nuclei of brainstem or lateral parts of spinal cord lateral parts of spinal cord gray matter from S2-S4gray matter from S2-S4 Preganglionic axons Preganglionic axons

from brain pass to from brain pass to terminal ganglia through terminal ganglia through cranial nerves III, VII, IX cranial nerves III, VII, IX and Xand X

Preganglionic axons Preganglionic axons from sacral region pass from sacral region pass through through pelvic nervespelvic nerves to terminal gangliato terminal ganglia

► Terminal gangliaTerminal ganglia located located near organ innervated or near organ innervated or embedded in wall of organembedded in wall of organ

Sympathetic vs Sympathetic vs parasympathetic parasympathetic

►Actions on different organsActions on different organs

Sympathetic vs Sympathetic vs parasympathetic parasympathetic

►Drugs acting on receptors Drugs acting on receptors

Parasympathetic

Sympathetic

salbutamol

Sympathetic vs Sympathetic vs parasympathetic parasympathetic

►Reflexes in different systems Reflexes in different systems

ANS reflexesANS reflexes

► CVS: CVS: baroreceptor reflexbaroreceptor reflex Control of heart rateControl of heart rate chemoreceptor reflexchemoreceptor reflex

► GIT: GIT: GIT secretions and motility GIT secretions and motility

► Other:Other: Urinary bladder controlUrinary bladder control Sexual reflexesSexual reflexes SweatingSweating Other visceral reflexes Other visceral reflexes