Physiology of ANS - Parasympathetic NS-1 Lecture Notes PDF
Document Details
Uploaded by DependableBarbizonSchool7682
KSIU School of Medicine
2024
Sherif W. Mansour
Tags
Summary
These lecture notes cover the parasympathetic nervous system. They discuss its role in anabolic activities and the conservation of body energy. The notes are organized into different parts, outlining the parasympathetic cranial and sacral outflows, and the functions of specific cranial nerves such as the oculomotor, facial, glossopharyngeal, and the associated ganglia. The document also includes diagrammatic representations of the human eye and associated nerves.
Full Transcript
Physiology of ANS- Parasympathetic NS-1 Sherif W. Mansour Prof. of physiology KSIU School of medicine 2024 1 The Parasympathetic nervous System It is the part of the autonomic nervous system, which deals with the anabolic activities and lead to...
Physiology of ANS- Parasympathetic NS-1 Sherif W. Mansour Prof. of physiology KSIU School of medicine 2024 1 The Parasympathetic nervous System It is the part of the autonomic nervous system, which deals with the anabolic activities and lead to conservation of body energy. It is also called the Cranio-sacral division according to its origin. Parasympathetic N.S is divided into: 1-Parasympathetic cranial outflow -Parasympathetic fibers are found in the cranial nerves III «Oculomotor», VII «Facial», IX «Glossopharyngeal» and X «Vagus» 2-Parasympathetic Sacral outflow -Parasympathetic fibers arise from LHCs of sacral 2,3 &4 segments of the spinal cord. Oculomotor nerve ( III) Arise From the Edinger-Westphal nucleus in the midbrain The preganglionic fibers relay in the ciliary ganglion. The postganglionic fibers run in the short ciliary nerves. These fibers produce: a) Contraction of the constrictor pupillae M. → narrowing of the pupil. (miosis). b) Contraction of the ciliary muscle: → relaxation of suspensory ligaments, ↑ convexity of lense, causing increased power of the lens which is very useful in near vision accommodation. Facial nerve (VII) Supply : the lacrimal, nasal and Submandibular salivary glands Preganglionic fibers: arise from the Superior salivary nucleus in pons Relay : Fibers that supply the lacrimal and nasal glands relay in The Sphenopalatine ganglion (collateral) Fibers that supply the Submandibular gland relay in the Submandibular ganglion (collateral) Functions: These fibers supply the Salivary glands and produce True secretion (Large in volume, less in enzymes and watery) also produce vasodilatation. True Secretion The Glosso-pharyngeal (IX) Supply the parotid salivary gland Preganglionic fibers arise from the inferior salivary nucleus (in medulla) relay in the Otic ganglion (collateral) Postganglionic fibers Supply the Parotid (largest) salivary gland. Functions: a) True secretion (Large in volume, less in enzymes and watery) b) Vasodilatation of blood vessels. N.B Nerve supply to salivary glands arise from Facial nerve ( to Submandibular and sublingual glands) and from Glosso-pharyngeal nerve (to parotid gland) Thank You 11
