Autonomic. Nervous System

Size: px

Start display at page:

Download "Autonomic. Nervous System"

Nora Nancy Alexander
6 years ago
Views:

1 Autnmic Nervus System Cmpiled by Campbell M Gld (2006) CMG Archives IMPORTANT The health infrmatin cntained herein is nt meant as a substitute fr advice frm yur physician, r ther health prfessinal. The fllwing material is intended fr general interest nly; and it shuld nt be used t diagnse, treat, r cure any cnditin whatever. If yu are cncerned abut any health issue, symptm, r ther indicatin, yu shuld cnsult yur regular physician, r ther health prfessinal. Cnsequently, the Authr cannt accept respnsibility fr any individual wh misuses the infrmatin cntained in this material. Thus, the reader is slely respnsible fr all f the health infrmatin cntained herein. Hwever, every effrt is made t ensure that the infrmatin in this material is accurate; but, the Authr is nt liable fr any errrs in cntent r presentatin, which may appear herein. Intrductin The autnmic nervus system (parasympathetic nervus system, sympathetic nervus system, vegetative nervus system) is the part f the nervus system that regulates vital functins f the bdy that are nt cnsciusly cntrlled (invluntary). It includes the activity f the heart, the smth muscles (e.g. digestive muscles), and the glands. It has tw divisins: 1) The Sympathetic Nervus System which speeds up heart rate, narrws bld vessels, and raises bld pressure. 2) The Parasympathetic Nervus System which slws heart rate, increases intestinal and gland activity, and relaxes ring-like muscles that clse passages (sphincters). Sympathetic Nervus System The general prperties f the sympathetic nervus system includes: Mediates the bdy's respnse t activity, stress, danger, r envirnmental challenge. The verall pattern f sympathetic activatin is typified by the fright, fight r flight reactin t danger. Its respnses include: Increased Heart Rate and Cntractility Dilatin f brnchiles fr easier breathing 1

2 Cnstrictin f arteriles in skin, digestive system, and nn-exercising muscles Inhibitin f digestive functins Widening f pupils Increased glucse in bld due t glycgenlysis in liver Increased fatty acid in bld frm adipse tissues Pilerectin Cld sweat (stimulated sweating with cnstricted skin arteriles) Invlved in expending energy Originates in the thracic and lumbar spinal crd Intermediate synapses near spinal crd, far frm target rgan. Mst f the synapses are in the paravertebral ganglia near the spinal crd. Preganglinic fibres are shrt, pstganglinic are lng Sympathetic neurns branch extensively. One cell may innervate many target cells, leading t mre generalized sympathetic respnses in the bdy The Sympathetic system can als act selectively in sme reflexes Primary target tissues are: Cardivascular system Lungs Smth muscle in all rgans Sme glands (sweat, salivary, and digestive) Metablic tissue (fat cells, liver) Sympathetic stimulatin can cause excitatin f sme tissues, inhibitin f thers Fr example, cntractin f arterilar smth muscle and relaxatin f brnchilar smth muscle are bth due t sympathetic stimulatin (Pictures belw - Sympathetic Nervus System) 2

3 Legends (abve): A - Superir Cervical Ganglin B - Celiac Ganglin C - Superir Mesenteric Ganglin D - Inferir Mesenteric Ganglin The clured circles represent the paravertebral ganglinic chain 3

Parasympathetic Nervus System The general prperties f the Parasympathetic Nervus system include: Respnsible fr 'husekeeping' functins f the bdy, many f which are vital fr life Invlved in cnservatin r

4 Parasympathetic Nervus System The general prperties f the Parasympathetic Nervus system include: Respnsible fr 'husekeeping' functins f the bdy, many f which are vital fr life Invlved in cnservatin r restratin f energy ('rest and digest') Parasympathetic cells riginate in the brainstem and sacral segments f the spinal crd The intermediate synapse is in (r near) the target rgan Little branching f the neurns is fund (ne neurn innervates just a few target cells). This gives specific, fine cntrl fr regulatin. N massive discharges Primary targets include: Heart (atria) Gastrintestinal system Excretry rgans Excrine glands Eye (cnstrictin f pupils, etc) Genitalia 4

5 Des nt innervate structures in the bdy wall (i.e. muscle and skin), nr mst bld vessels. (Pictures belw - Parasympathetic Nervus system) Nte: Unlike the Sympathetic Nervus System, the Parasympathetic Nervus System preganglinic neurnes synapse with nly a relatively few pstganglinic neurnes Fr this reasn they are much mre precise and lcalised in their effects End 5

6 /1

Imaging tests allow the cancer care team to check for cancer and other problems inside the body.

Imaging tests allow the cancer care team to check for cancer and other problems inside the body. IMAGING TESTS This infrmatin may help answer sme f yur questins and help yu think f ther questins that yu may want t ask yur cancer care team; it is nt intended t replace advice r discussin between yu