INTRODUCTION TO AUTONOMIC PHARMACOLOGY: Part VI Interaction of drugs with the autonomic nervous system

SYMPATHOMIMETICS: Drugs that facilitate or mimic some or all of the actions of the sympathetic nervous system. Direct Acting Indirect Acting Drugs that facilitate NE release Drugs that block NE uptake  -adrenergic agonists  -adrenergic agonists

Ganglionic blocking drugs Centrally acting sympatholytics NE depleting drugs Drugs that inhibit NE synthesis Adrenergic neuronal blocking drugs  -adrenergic antagonists  - adrenergic antagonists SYMPATHOLYTICS: Drugs that reduce or inhibit some or all of the actions of the sympathetic nervous system.

PARASYMPATHOMIMETICS (CHOLINOMIMETICS): Drugs that facilitate or mimic some or all of the actions of the parasympathetic nervous system. Muscarinic receptor agonists Anticholinesterases

PARASYMPATHOLYTICS (ANTICHOLINERGICS): Drugs that reduce or inhibit some or all of the actions of the parasympathetic nervous system. Muscarinic receptor antagonists Ganglionic blocking drugs

Predicting Responses of Drugs that Interact with the Autonomic Nervous System

Baroreceptor Reflex

BP (mmHg) SNA (Units) PSNA (Units) HR (bpm) Time (minutes) Phenylephrine Histamine

Predicting Responses  1 &  2  1,  2,  1 &  2  1,  1 &  2

ACH (2  g) ACH (5 mg) ACH (50  g) ACH (5 mg) Heart RateBlood Pressure (Atropine: Muscarinic Receptor Antagonist) ( Hexamethonium : Neuronal Nicotinic Receptor Antagonist)