1. Copyright (c) 2004 Elsevier Inc. All rights reserved. Physiology of the Peripheral Nervous System Chapter 13

2. Copyright (c) 2004 Elsevier Inc. All rights reserved. Physiology of the Peripheral Nervous System The divisions of nervous system Central nervous system –Brain and spinal cord Peripheral nervous system –Somatic motor –Autonomic Parasympathetic Sympathetic

3. Copyright (c) 2004 Elsevier Inc. All rights reserved. Parasympathetic Nervous System (PNS) The regulatory functions of PNS affect these sites Heart rate Gastric secretions Bladder and bowel Vision Bronchial smooth muscle

4. Copyright (c) 2004 Elsevier Inc. All rights reserved. Sympathetic Nervous System Main functions of the SNS Regulation of cardiovascular system Regulation of body temperature Implementation of “fight or flight” reaction

5. Copyright (c) 2004 Elsevier Inc. All rights reserved. Transmitters of the Peripheral Nervous System (PNS) Principal neurotransmitters of PNS are Acetylcholine Norepinephrine Epinephrine Dopamine

6. Copyright (c) 2004 Elsevier Inc. All rights reserved. Receptors of the Peripheral Nervous System Cholinergic –Mediated by acetylcholine Adrenergic –Mediated by norepinephrine and epinephrine

7. Copyright (c) 2004 Elsevier Inc. All rights reserved. Subtypes of Cholinergic and Adrenergic Receptors Cholinergic receptor –Nicotinic n –Nicotinic m –Muscarinic Adrenergic –Alpha 1 and alpha 2 –Beta 1 and beta 2 –Dopamine

8. Copyright (c) 2004 Elsevier Inc. All rights reserved. Functions of Cholinergic Receptor Subtypes Nicotinic n (neuronal) –Promotes ganglia transmission –Promotes release of epinephrine Nicotinic m (muscle) –Contraction of skeletal muscle Muscarinic –Activates parasympathetic nervous system

9. Copyright (c) 2004 Elsevier Inc. All rights reserved. Alpha 1 –Vasoconstriction –Ejaculation –Contraction of bladder neck and prostate Alpha 2 –Located in presynaptic junction –Minimal clinical significance Functions of Adrenergic Receptor Subtypes

10. Copyright (c) 2004 Elsevier Inc. All rights reserved. Functions of Adrenergic Receptor Subtypes (cont.) Beta 1 Heart –Increases heart rate force of contraction velocity of conduction in AV node Kidney –Renin release

11. Copyright (c) 2004 Elsevier Inc. All rights reserved. Beta 2 –Bronchial dilation –Relaxation of uterine muscle –Vasodilation –Glycogenolysis Dopamine –Dilates renal blood vessels Functions of Adrenergic Receptor Subtypes (cont.)