The sympathetic and the parasympathetic nervous system Zsuzsanna Tóth, PhD Institute of Anatomy, Histology and Embryology Semmelweis University The role of the autonomic nervous system Claude Bernard • „milieu intérieur” concept; every organism lives in its internal environment that is constant and independent form the external environment Walter Bradford Cannon homeostasis; • an extension of the “milieu interieur” concept • consistence in an open system requires mechanisms that act to maintain that consistency • steady-state conditions require that any tendency toward change automatically meets with factors that resist that change • regulating systems that determine the homeostatic state : o autonomic nervous system ( sympathetic, parasympathetic, enteral) o endocrine system General structure of the autonomic nervous system craniosacral thoracolumbar Anatomy Neurotransmittersof the gut autonomic nervous system. symp. gangl pregangl. fiber pregangl. postgangl. fiber fiber (PoR) PoR enteral ganglion PoR PoR smooth muscle smooth muscle Kuratani S Development 2009;136:1585-1589 Sympathetic activation: Fight or flight reaction • energy mobilization • preparation for escape, or fight vasoconstriction • generalized Parasympathetic activation: adrenal • energy saving and restoring • „rest and digest” system • more localized vasoconstriction Paravertebral ganglia and the sympathetic chains pars cervicalis superius ganglion medium cervicale stellatum pars vertebrae • from the base of the skull to the caudal end thoracalis thoracalis of the sacrum • paravertebral ganglia (ganglia trunci sympathici) • rami interganglionares pars vertebrae • the two chains fuses at the ganglion impar abdominalis lumbalis sacrum pars pelvina foramen sacralia anteriora ganglion impar Anatomy of the cervical part of the sympathetic trunk superior cervical ganglion • behind the seath of the carotid, fusiform ggl. cervicale superius • IML T1-3 vegetative motoneurons- preganglionic fibers truncus symp. pars cephalica middle cervical ganglion a. vertebralis in the fossa scalenotrachealis ggl. cervicale medium ansa subclavia a. vertebralis • connects the middle cervical and the stellate ansa subclavia ganglia • a loop of the trunk around the subclavian artery a. subclavia stellate ganglion ggl. cervicale inferius • lies superior to the neck of the first rib ggl. stellatum T1 ganglion • trunci symp. formed by the fusion of the inferior cervical ganglion and the first thoracic ganglion (80%) Sympathetic efferents divergence , IML paravertebral ganglia T1-L2(3) (sympathetic chain) preganglionic : postganglionic ≈ 1:30 prevertebral ganglia target organ target organ target organ adrenal medulla Rami communicantes white rami communicantes: • distal radix dorsalis • myelinated, ganglion spinale (DRG) • preganglionic fibers and ramus dorsalis nervus spinalis visceral afferents interneurons • only at T1-L2 spinal nerves IML ramus ventralis • run longitudinal within the nervus spinalis trunk visceral efferents gray rami communicantes: radix ventralis • proximal ramus communicans griseus • non-myelinated, postgangionic fibers ramus communicans • postganglionic fibers albus • each spinal nerves has one preganglionic and afferent fibers visceral afferents visceral afferents: ganglion • with sympathetic efferents via viscera trunci sympathici the r.c. albus, • with parasympathetic efferents • terminate in the DRG Parietal sympathetic efferents IML paravertebral ganglia T1-L2(3) (sympathetic chain) head, body, limbs: vasomotor, sudomotor, piloerrector, innervation Sympathetic innervation of the skin pathway: • IML→preganglionic fiber, spinal nerve→ white ramus→ paravertebral ganglion → postganglionic fiber, grey ramus→ spinal nerve→ skin functions: • vasomotor, sudomotor, piloerrector –vasoconstriction, perspiration, goose bumps intermediolateral Paravertebral Spinal nerve Target area cell column (IML) ganglion ggl. cerv. superius nn. C1-4 (cervical plexus) head, neck T1-7 ggl. cerv. medius nn. C4-7 (plexus brachialis) upper limbs ggl. stellatum nn. C7-T1 (plexus brachialis) upper limbs T1-11 T1-11 nn. T1-11 (nn. intercostales) body L1-4 plexus lumbalis, plexus hips, lower limbs T8-L2 ischiadicus S1-4(5) plexus sacralis hips, perineum, lower limbs Superior cervical ganglion I. sympathetic plexus parasympathetic caroticus m. internus tarsalis Preganglionic fibers ggl. cervicale superius • IML upper thoracic segments (spinociliar center) r m. dilatator m. orbitalis • Relay: SCG a ggl. ciliare ramus c. m. sphincter albus ramus c. Postganglionic fibers : griseusm m. ciliares paravertebral ganglion nucleus u salivatorius • internal and external carotid plexuses superior s • jugular plexus n. facialis ggl. submandibulare plexus Functions: caroticus externus chorda • vaso- and sudomotor innervation of the head tympani ggl. cervicale superius • dilatation of the pupil (relaxed state) ggl. spinale • raising the upper eyelid (m. tarsalis,) n. spinalis • m. orbitalis • viscous salivary secretions radix glandula ventralis sublingualis • glandula vasomotor innervation of the pia mater submandibularis • fibers to the heart, pharynx, corpus pineale Superior cervical ganglion II-parotid and lacrimal glands sympathetic parasympathetic auriculotemporal parotid gland nerve Otic ganglion ggl. cervicale superius tympanic plexus plexus lesser caroticus petrosal n. externus tympanic nerve (CN IX/1) Sympathetic innervation: CN IX Same pathway as in case of the n. salivatorius submandibular and sublinguar glands inferior plexus caroticus n. lacrimalis externus lacrimal n. zygomaticus ggl. pterygopalatinum gland ggl. cervicale superius n. petrosus major (CN VII/1) n. salivatorius superior Horner’s syndrome Symptoms: • ptosis (drooping of the upper eyelid), • miosis (a constricted pupil) • enophtalmos (sinking of the eyeball in the orbit) • anhydrosis (decreased sweating over the ipsilateral forehead) • dilation of arterioles of the skin • ciliospinal reflex (pupillary-skin reflex) is absent hypothalamus n. nasociliaris (III).n m. dilatator ggl. cerv. sup. g centrum ciliospinale Hypothalamus Mesencephalon Spatium parasympathetic Spatium perichoroideale N. Westphal- perichoroideale-idegek Edinger (III.) M. ciliaris, M. sphincter pupillae Nn. ciliares breves r. inf. n. oculomotorii radix brevis (motoria) Nn. ciliares longi Pons Ganglion trigeminale n. nasociliaris radix longa (sensoria) Nucleus Ggl. ciliare sensorius Lemniscus n. V. Nn. ciliares longi trigeminalis Plexus caroticus int. somatosensory Plexus ophthalmicus Conjunctiva, Cornea, Radix sympathica M. dilatator pupillae, M. tarsalis, M. orbitalis sympathetic Medulla Autonomic innervation of the ciliary body and Ganglion cervicale spinalis muscles in the eye superius From prof. Ágoston Szél Parasympathetic innervation of the pupil plexus caroticus m. tarsalis internus Edinger-Westphal nucleus ggl. cervicale superius short ciliary nerves r m. dilatator (radial m) a ciliary ganglion ramus c. ramus c. m. sphincter mgriseus albus (circular m.) u m. ciliaris s Preganglionic fibers: Edinger-Westphal nucleus, CN III Relay: ciliary ganglion Postganglionic fibers: short ciliary nerves Function: constriction of the pupil and the ciliary muscle (accomodation) Parasympathetic innervation the submandibular, sublingual and lacrimal glands n. salivatorius sympathetic parasympathetic superior ggl. n. facialis plexus caroticus submandibulare Submandibular and sublingual glands externus Chorda Preganglionic fibers: ggl. cervicale superius tympani CN VII./3 • superior salivatory nucleus, chorda ggl. spinale r n. spinalis tympani (CN VII/3) a m Relay: submandibular ganglion radix glandula Function: secretion of watery saliva ventralis u sublingualis glandula s submandibularis n. Lacrimal gland lacrimalis Preganglionic fibers: ggl. • superior salivatory nucleus, greater lacrimal n. pterygopalatinum gland ggl. cervicale superius zygomaticus petrosal nerve (CN VII/1) Relay: pterygopalatin ganglion n. petrosus major Postganglionic fibers: zygomatic nerve, (CN VII/1) n. salivatorius communicating branch, lacrimal nerve superior Function: secretion of tears Parasympathetic innervation of the parotid gland parotid gland auriculotemporal nerve Otic ganglion ggl. cervicale superius tympanic plexus caroticus plexus lesser externus petrosal n. tympanic nerve (CN IX/1) CN IX n. salivatorius inferior Preganglionic fibers: inferior salivatory nucleus, glossopharyngeal nerve (CN IX) tympanic nerve (CN IX/1), tympanic plexus, lesser petrosal nerve Relay: otic ganglion Postganglionic fibers: auriculotemporal nerve Sympathetic innervation of the heart and lung sympathetic parasympathetic Heart: ggl. • Preganglionic fibers: IML T1-T4 cervicale • Relay: cervical ganglia and T1-4 ganglia of the trunk sup. ggl. • Postganglionic fibers: cardiac plexus -SA and AV nodes, atrium n. dorsalis nervi cervicale vagi and ventricle - heart rate and force increases med. n. ambiguus ggl. cervicale Lung: inf. heart plexus cardiacus • Preganglionic fibers: IML T1-T4 • Relay: T1-T4 ganglia of the trunk , stellate ganglion n. vagus • Postganglionic fibers: pulmonal plexus -bronchodilatation ggl. 1 Upper third of the esophagus: • Preganglionic fibers: IML T1-T6 • Relay: stellate ganglion • Postganglionic fibers: cardiac and pulmonal plexuses r.c. albus Others: lung plexus pulmonalis • ggl. cervicale medium: larynx, pharynx, thyroid-vasoconstriction • ggl. stellatum - n. vertebralis: radix ventr. o upper limbs (vaso- and sudomotor, piloerrector) ggl. 4 Parasympathetic innervation of the heart and lung