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

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

Adrenergicneuronal

blocking drugs

-adrenergicantagonists

-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

antagonistsGanglionic blocking

drugs

Predicting Responses of Drugs that

Interact with the Autonomic

Nervous System

Baroreceptor Reflex

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 (50 g)

ACH (5 mg)

Heart Rate Blood Pressure

(Atropine: Muscarinic Receptor Antagonist)

(Hexamethonium: Neuronal Nicotinic Receptor Antagonist)