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Neurophysiology Autonomic Nervous System Dr. Noha Osama Dr. Asmaa Tarek Lecturer of Physiology Faculty of Medicine 1  General organization of nervous system Nervous System Central Nervous...

Neurophysiology Autonomic Nervous System Dr. Noha Osama Dr. Asmaa Tarek Lecturer of Physiology Faculty of Medicine 1  General organization of nervous system Nervous System Central Nervous Peripheral Nervous System System Somatic Autonomic (control Brain Spinal Cord (control involuntary muscles voluntary &glands) muscle) Sympathetic Parasympathetic 2  Sympathetic Parasympathetic Preganglionic …. …. Neurons Acetylcholine …. …. Acetylcholine …. …. …. …. (Ach) (Ach) Postganglionic Neurons Norepinephrine Acetylcholine (NE) (Ach) …. …. …. …. 3 4  ANS receptors Adrenergic Cholinergic Muscarinic Nicotinic α1, α2 ,β1, β2 receptors: receptors: M1 , M2 , M3 N1 , N2 5 Let's apply  Case study Helen is a 51-year-old homemaker who experienced frequent “attacks” of heart racing and bounding; throbbing headache and visual disturbances; she felt hot, but her hands and feet were cold. On examination, her blood pressure was severely elevated at 200/110, her heart rate was increased at 110 beats/min. To rule out a pheochromocytoma the physician ordered a 24- hour urine measurement of vanillylmandelic acid (VMA) which were positive. A computed tomographic scan confirmed that Helen had a 3- cm mass on her right adrenal gland. While awaiting surgery she was given, an α1-adrenergic antagonist and a low dose of propranolol (a β-adrenergic antagonist).  What is pheochromocytoma and its etiology ? What are the What is its possible treatment pathophysiology methods? and manifestation?  What is Pheochromocytoma and its etiology? It is a tumor of adrenal mrdulla that produce large amount of catecholamines and mainly adrenaline (epinephrine) and noradrenaline (norepinephrine). This causes exaggerated sympathetic effects due to adrenergic stimulation.  Pathophysiology of pheochromocytoma Expected management 1) Medications: For a pheochromocytoma, alpha blockers are used first to return blood pressure back to within normal limits. Once blood pressure is lowered, beta blockers can help control a rapid or irregular heartbeat. Both alpha and beta blockers are used in preparation for surgery. 2) Surgically: laparoscopic adrenalectomy.  Horner's syndrome  Horner's syndrome Horner's syndrome: is a combination of signs and symptoms caused by lesion along the sympathetic pathway that originates in the hypothalamus. that supplies the head, eye, and neck. which is a result of many causes, such as 1-Carotid artery dissection ; a tumor in neck or chest cavity 2- lesion in midbrain, brain stem, upper spinal cord, neck, or eye orbit 3- Inflammation affecting the lymph nodes of the neck 4- Surgery or trauma to the neck and the upper spinal Symptoms: Horner syndrome usually affects only one side of the face. Common signs and symptoms include: 1- Miosis (ie, constricted pupil) 2- Ptosis (ie, dropping of upper eye lid) 3- Anhydrosis (loss of hemifacial sweating) Diagnosis Diagnosis Horner’s syndrome is diagnosed clinically by: Ptosis Misois Anhydrosis And for confirmation 1. X-rays 2. MRI 3. CT scan  Expected Management There is no a specific treatment for Horner’s syndrome. Instead, the condition that caused Horner’s syndrome will be treated. Supportive treatment.