Autonomic Nervous System Functions PDF

Wondershare PDFelement Autonomic nervous system Dr. Hader I. Sakr Associate professor, Medical Physiology  ‫‪Wondershare‬‬ ‫‪PDFelement‬‬ ‫بسم هللا الرمحن...

Wondershare PDFelement Autonomic nervous system Dr. Hader I. Sakr Associate professor, Medical Physiology  ‫‪Wondershare‬‬ ‫‪PDFelement‬‬ ‫بسم هللا الرمحن الرحمي‬ ‫اَّلل‬ ‫و‬ ‫ۗ‬ ‫اَّلل‬ ‫ُ‬ ‫ُك‬‫ُ‬ ‫م‬‫ل‬‫ِّ‬ ‫﴿ َوات َّ ُقوا َّ َ‬ ‫اَّلل ۖ َوي ُ َع ُ َّ ُ َ َّ ُ‬ ‫َش ٍء عَ ِّل ممي﴾‬ ‫ك َْ‬ ‫ِّب ُ ِّ‬  Wondershare PDFelement Learning objectives: Discuss Functions of ANS ON: 1. Head & neck 2. Chest 3. Abdomen 4. Pelvis Horner’s syndrome The enteric nervous system  Wondershare PDFelement Functions of ANS  Wondershare PDFelement Functions of ANS  Wondershare PDFelement Functions of ANS  Wondershare PDFelement Functions of ANS  Wondershare PDFelement Functions of ANS  Wondershare PDFelement Functions of ANS - 75% of all parasympathetic nerve fibers are in the Vagus nerves (X). - Vagal supply to the heart arises from nucleus ambiguous, while the remaining from dorsal motor nucleus.  Wondershare PDFelement Functions of ANS  Wondershare PDFelement Functions of ANS  Wondershare PDFelement Functions of ANS  Wondershare PDFelement Functions of ANS II: The preganglionic neurons leave paravertebral chain without rely as greater (abdomen) and lesser (pelvis) splanchnic nerves to relay in collateral ganglia: From T5-9 → celiac ganglion → stomach, liver, pancreas and spleen. From T9-10 → adrenal medulla. From T10-12 → superior mesenteric ganglion → small intestine and proximal colon. III: Wall of the stomach, small intestine and proximal large intestine (abdomen). IV: Cardiac, pyloric and ileocecal (abdomen).  Wondershare PDFelement Functions of ANS  Wondershare PDFelement Functions of ANS  Wondershare PDFelement Functions of ANS  Wondershare PDFelement Functions of ANS II: From T12, L1-3 → inferior mesenteric → distal colon, bladder and sex organs. → aorticorenal ganglia → kidney. III: distal large intestine and rectum (pelvis). IV: internal anal (pelvis). V: They run as the: pelvic visceral nerve (nervi erigentes).  Wondershare PDFelement Functions of ANS N.B: - ANS can double the HR within 3-5 sec. and the ABP within 10-15 sec. It can also lower the ABP enough to cause fainting within 10-15 sec. - Sympathetic discharge is decreased in fasting animals (decreases blood pressure and MR) and increased when fasted animals are again fed. - The parasympathetic supply to the upper ureter is from the vagus nerve, while the lower portion is from nervi erigentes  Wondershare PDFelement Functions of ANS  Wondershare PDFelement Functions of ANS Wondershare PDFelement  Wondershare PDFelement Horner’s syndrome  Wondershare PDFelement Horner’s syndrome Horner's Syndrome: - Rare disorder due to lesion on one side of the cervical sympathetic chain with no specific treatment. - It results from interruption of preganglionic or postganglionic* sympathetic innervation to the face. - The problem can result from lesion in the brainstem, injury to the nerves or the carotid artery, a stroke, or a tumor in the lung. *: If a drug that causes release of catecholamine stores (e.g., hydroxyl-amphetamine) is administered and the constricted pupil dilates → preganglionic damage, if it does not dilate → postganglionic damage mainly.  Wondershare PDFelement Horner’s syndrome - In most cases the problem is unilateral, with symptoms occurring only on the side of the damage: 1. The superior eye lid drops (Ptosis). 2. The pupil remains persistently constricted to a smaller diameter (Miosis) than that of the opposite eye. 3. Sweating can’t occur on the side of the face and head affected (Anhydrosis). 4. Persistent dilatation of the blood vessels of head & neck → the skin becomes warm and red. 5. In man, the enophthalmos is apparent due to small palpebral fissure.  Wondershare PDFelement The enteric nervous system  Wondershare PDFelement The enteric nervous system - NS It is considered as the third division of the ANS. - Located all the way from the esophagus to the anus. - It contains as many neurons as the entire spinal cord. - It is sometimes referred to as a “mini- brain” as it contains all nervous system elements. - It is composed of two well-organized neural plexuses:  Wondershare PDFelement The enteric nervous system 1. NS The myenteric plexus (motor, between longitudinal & circular muscle layers): is involved in control of digestive tract motility. 2. The submucosal plexus (sensory-motor, between the circular muscle & luminal mucosa): senses the environment of the lumen and regulates gastrointestinal blood flow and epithelial cell function. - Although the ENS can function autonomously, normal digestive function often requires communication between the CNS & ENS. - Parasympathetic and sympathetic nerves (ANS) connect the CNS to the ENS or directly to the digestive tract. Wondershare PDFelement  Wondershare PDFelement Conclusion The ANS could be divided into sympathetic, parasympathetic and enteric Nervous systems. The entric nervous system is the connection between the CNS and the ANS. Both sympathetic and parasympathetic nervous systems supplies the head & nech, chest, abdomen, and pelvis. In each region they have origin, relay ganglion, effector organs and variable effects Horner’s syndrome arises due to unilateral lesion of the cervical sympathetic chain  Wondershare PDFelement References Guyton and Hall, 13th edition. Unit II(6); 81-2. Ganong’s review of medical physiology 25th ed. Section I(5); 107-10.  Wondershare PDFelement Thank You