Autonomic Nervous System 4 PDF

Field of Medicine Medicine Program Lecture : (Autonomic Nervous System 4 ) Dr : (Mohamed Talal) Date : 19 /10 /2024  sympathetic nervous system: (Biology – forums , copy rights ) sympathetic nervous system: Adrenergic receptors α...

Field of Medicine Medicine Program Lecture : (Autonomic Nervous System 4 ) Dr : (Mohamed Talal) Date : 19 /10 /2024  sympathetic nervous system: (Biology – forums , copy rights ) sympathetic nervous system: Adrenergic receptors α β α1 α2 β1 β2 β3 sympathetic nervous system: α receptors : α1 α2 (contraction ) (relaxation ) Site Eye ( dilator pupillae Wall of GIT muscle ). Arterioles. GIT sphincters. Internal urethral sphincter. Internal anal sphincter. sympathetic nervous system: β receptors : Β1 β2 β3 ( stimulation ) ( relaxation ) Site Heart Wall of bronchi Adipose tissue Wall of rectum ( lipolysis and Wall of urinary bladder thermogenesis ) sympathetic nervous system: General rule Sympathetic nervous system causes vasoconstriction of all blood vessels except those supplying the heart and skeletal muscles.  Divisions of Autonomic nervous system Parasympathetic nervous system : parasympathetic nervous system Origin : cranio-sacral Cranial outflow Sacral outflow Oculomotor nerve (head and pelvic branches of S2-S3 and S4 neck) (pelvis ) Facial nerve (head and neck) Glossopharyngeal nerve (head and neck) Vagus nerve ( thorax – abdomen ) Parasympathetic nervous system Effect on head and neck : Oculomotor nerve (3rd cranial nerve): origin : Edinger – Westphal nucleus of midbrain relay : ciliary ganglion Action : eye : pupil constriction ( contraction of constrictor pupillae muscle ) Parasympathetic nervous system Effect on head and neck : Facial nerve: (7th cranial nerve) origin : superior salivary nucleus in pons relay : sphenopalatine ganglion Action : On sublingual and submandibular glands : Increases their secretions Parasympathetic nervous system Effect on head and neck : Glossopharyngeal nerve : ( 9th cranial nerve ) origin : inferior salivary nucleus in medulla relay : otic ganglia Action : On parotid gland : Increases its secretions