1 / 46

Sympathetic Nervous System

Sympathetic Nervous System. Nervous System. CNS. PNS. Brain Spinal Cord. Autonomic NS. Somatic NS. Sympathetic. Parasympathetic. CNS. ACh. C. M. N. ACh. T. ACh.  1. NE. N. L. NE.  1.  2. S. ACh. SM. N. CNS. ACh. C. M. N. ACh. T. ACh.  1. NE. N. L. NE.

zenia-chan
Télécharger la présentation

Sympathetic Nervous System

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Sympathetic Nervous System

  2. Nervous System CNS PNS Brain Spinal Cord Autonomic NS Somatic NS Sympathetic Parasympathetic

  3. CNS ACh C M N ACh T ACh 1 NE N L NE 1 2 S ACh SM N

  4. CNS ACh C M N ACh T ACh 1 NE N L NE 1 N EPI ACh 2 S ACh SM N

  5. CNS ACh C M N ACh T ACh 1 NE N L NE ACh 1 N SG ACh M 2 S ACh SM N

  6. Sympathetic Nervous System CNS (-) 2 C M T ACh 1 NE N L NE 1 N EPI ACh 2 S

  7. Dual Innervation Exceptions (only sympathetic) - blood vessels (only parasympathetic) - bronchioles (only parasympathetic) - ciliary muscles Predominant Tone Primarily parasympathetic NS Exceptions - blood vessels (sympathetic) - sweat glands (sympathetic cholinergic)

  8. Denervation Supersensitivity + Effect +++ Effect NT NT Before Denervation After Denervation

  9. Catecholamines NE EPI DA

  10. PRESYNAPTIC POSTSYNAPTIC NE - predominately removed from synapse via ‘re-uptake 1’ Metabolic Removal Re-uptake 2 Re-uptake 1 NE synthesis COMT MAO NE  /  Action NE MAO (-) 2 Receptor Binding

  11. Drug actions at presynaptic autonomic nerve terminals

  12. Adrenergic Receptors 1, 2, 1 NE 1, 2, 1, 2 EPI

  13. Adrenergic Receptors 1, 2, 1 NE 1, 2, 1, 2 EPI 1, 1, DA1 DA

  14. EFFECTS OF STIMULATING ADRENERGIC RECEPTORS SITEEFFECT HEART TACHYCARDIA and INCREASED CONTRACTILITY (1) VASCULATURE VASODILATION VASOCONSTRICTION (1,  2) (2) BRONCHORELAXATION (2) AIRWAYS IRIS MYDRIASIS (1) BLADDER DECREASED URINATION (2) GI TRACT DECREASED GI MOTILITY and SECRETIONS (2) UTERUS RELAXATION (2)

  15. contractile force heart rate 1 renin release vasodilation, TPR 2 vasoconstriction TPR 1, 2

  16. Drugs and Adrenergic Synapses

  17. CNS Adrenergic Agonists ACh C M N ACh T ACh 1 NE N L NE 1 N EPI ACh 2 S ACh SM N

  18. MIXED ADRENERGIC AGONISTS • Norepinephrine 1, 2, 1 • Epinephrine 1, 2, 1, 2 Dopamine DA1, 1, 1

  19. HR BP TPR

  20. MIXED ADRENERGIC AGONISTS • Norepinephrine (1, 2, 1) • Epinephrine (1, 2, 1, 2) Tx: ● Asthma (but there are better drugs) ● Anaphylactic shock ● Cardiogenic shock ● Prolong action of local anesthetics ● Topical hemostatic agent Dopamine (DA, 1, 1) Tx: ● CHF

  21. ALPHA AGONISTS - Phenylephrine (1) - Methoxamine (1) • - Oxymetazoline (1 and 2 in periphery) - Tetrahydrozoline (1) - Naphazoline(1) - Ephedrine/Pseudoephedrine (1) • - Clonidine (2, Tx site of action is CNS)

  22. Tx uses for ALPHA AGONISTS • Alpha-1 agonists Tx: ● Nasal decongestion ● Used in eye drops to ‘get the red out’ ●Hypotensive states Alpha-2 agonists Tx: ● Hypertension

  23. BETA AGONISTS and Tx uses Non-selective 1/2 - Isoproterenol Selective 1 • - Dobutamine Selective 2 • - Albuterol Tx: Cardiac stimulant • - Metaproterenol • - Terbutaline Tx: COPD, Asthma • - Isoetharine • - Bitolterol Tx: Inotropic agent • - Ritodrine Tx: Uterine relaxation

  24. NE EPI ISO HR BP TPR

  25. Dose-response effects produced by dopamine at different receptors

  26. CNS ADRENERGIC AGENTS • CNS : Tx antihypertensive effect • - Clonidine(2 agonist) - Guanabenz (2 agonist) - Guanfacine (2 agonist) - Methyldopa Converted in CNS to methylnorepinephrine (low efficacy 2 agonist)

  27. Sympathetic Nervous System CNS (-) 2 C M T ACh 1 (-) NE N (-) L NE 1 N EPI ACh 2 S 2

  28. CNS Adrenergic Antagonists ACh C M N ACh T ACh 1 X NE N L X NE 1 N EPI X ACh 2 S ACh SM N

  29. ALPHA ANTAGONISTS and Tx uses Nonselective 1 and 2 receptor antagonists - Phenoxybenzamine Non-competitive action • - Phentolamine Competitive action Tx: - DOC for overdose of alpha agonists - Management of pheochromocytoma - Dental use for reversal of local anesthetic action Selective 1 receptor antagonists - Prazosin - Terazosin(water soluble) Tx: Antihypertensive agents, Management of benign prostatic hypertrophy

  30. Adrenergic Influence on Vascular Smooth Muscle Tone VSMC 2 NE 1 NE Vasoconstriction (-) 2

  31. Adrenergic Influence on Vascular Smooth Muscle Tone EPI VSMC 2 Vasoconstriction NE 1 NE Vasoconstriction (-) 2

  32. Marked hypotensive response produced by dual 1 and 2 - Receptor Blockade on VSMC EPI VSMC X 2 Vasodilation X NE NE 1 Vasodilation (-) X 2 Phentolamine- 1 and 2 blockade

  33. Moderate hypotensive response produced by dual 1 and 2 - Receptor Blockade 0n VSMC EPI VSMC 2 Vasoconstriction X NE NE 1 Vasodilation (-) 2 Prazosin- selective 1 blockade

  34. BETA ANTAGONISTS ● Non-selective 1, 2 ● ‘Cardio’- Selective 1 • Atenolol • Propranolol • Metropolol Nadolol Esmolol Timolol Acebutolol(ISA) Pindolol ● Non-selective 1, 2, 1 Carteolol Intrinsic Sympathomimetic Activity Labetalol Carvedilol

  35. Beta Blocker Tx Uses: ●Congestive heart failure ● Hypertension ● Myocardial infarction ●Angina ●Migrane ● Arrhythmias ●Anxiety ●Stage fright

  36. INDIRECT ACTING ADRENERGIC AGONISTS Tyramine(dietary substance) Ephedrine Pseudoephedrine Amphetamine

  37. Amphetamine PRESYNAPTIC POSTSYNAPTIC Re-uptake 1 NE  /  Action NE Receptor Binding

  38. Amphetamine PRESYNAPTIC POSTSYNAPTIC Re-uptake 1 amphetamine NE NE (+)  /  Action Receptor Binding

  39. Uptake Blockers • Cocaine • Tricyclic Antidepressants

  40. Cocaine PRESYNAPTIC POSTSYNAPTIC Re-uptake 1 NE  /  Action NE Receptor Binding

  41. Cocaine PRESYNAPTIC POSTSYNAPTIC Re-uptake 1 cocaine X NE NE  /  Action Receptor Binding

  42. Neuronal Blockers • Reserpine Depletes NE stores by inhibiting vesicular uptake of NE; NE then metabolized by intra-neuronal MAO • Guanethadine Inhibits NE release, also causes NE depletion, and can damage NE neurons

  43. Monoamine Oxidase (MAO) Inhibitors • Pargyline • Tranylcypromine Tyramine (or other drugs that promote NE release) may cause markedly increased blood pressure in patients taking MAO inhibitors

More Related