PANS (parasympathetic pt. of ANS)
- The PSNS is commonly associated with the “rest and digest” response, as it is involved in slowing down heart rate, relaxing sphincter muscles in the gastrointestinal and urinary tracts, and increasing intestinal and gland activity. Essentially, it conserves energy and regulates basic bodily functions such as digestion and urination.
Divison :
- The PANS is divided into a :
1. Cranial part.
- 1.1 Oculomotor nerve (nervus oculomotorius)
- – innervates the ciliary body and sphincter pupillae
- 1.1.1 Ciliary ganglion (ganglion ciliare) – is located in the orbit
- 1.2 Facial nerve (nervus facialis)
- 1.2.1 Submandibular ganglion (ganglion submandibulare)
- – is located in the submandibular triangle
- – innervates the submandibular, sublingual and lingual glands
- – fibres from the chorda tympani reach the submandibular ganglion via the lingual nerve
- 1.2.2 Pterygopalatine ganglion (ganglion pterygopalatinum)
- – is located in the pterygopalatine fossa
- – innervates the lacrimal, palatine, nasal and nasopharyngeal glands
- 1.3 Glossopharyngeal nerve (nervus glossopharyngeus)
- – innervates the parotid gland
- – preganglionic fibres reach the otic ganglion (ganglion oticum) via the tympanic nerve, tympanic plexus (plexus tympanicus) and lesser petrosal nerve
- – the postganglionic fibres travel to the parotid gland via the auriculotemporal nerve and to the buccal glands via the buccal nerve
- 1.3.1 Otic ganglion (ganglion oticum)
- – is located in the infratemporal fossa
- 1.4 Vagus nerve (nervus vagus)
- – innervates of smooth muscle, glands, internal organs and myocardium
* The boundary btw. cranial & sacral innervation lies at the left colic flexure (Cannon - Böhm point).
2. Sacral part :
- Includes the 2nd to 4th sacral nerves.
- Preganglionic fibers originate in the spinal segments S2-S4.
- These fibers travel as the sacral splanchnic nerves to the inferior hypogastric plexus.