pharmacology exam 1- Autonomic Nervous System

Autonomic Nervous System

Involuntary responses

sympathetic

fight or flight

parasympathetic

rest or digest

Function of the ANS

Respiratory rate, Heart rate, Blood pressure, Digestion

Sympathetic division

 Branches from the thoracic and lumbar segments of the spinal cord
 Presynaptic neuron is shorter and closer to the spinal cord

Parasympathetic division

 Branches from the cervical and sacral segments of the spinal cord
 Presynaptic neuron is longer and further from the spinal cord

Acetylcholine (ACh)

Responsible for “rest and digest”

Norepinephrine (NE)

Responsible for ‘fight or flight’

Anticholinergic

Agents that block or prevent the release of ACh

Adrenergic

Agents that stimulate a receptor to stimulate the release of norepinephrine

Antiadrenergic

agents that block a receptor from NE having an
effect

What is the primary function of the sympathetic nervous system in relation to the lungs?

causes bronchodilation (relaxation of airway smooth muscle)

How does the parasympathetic nervous system affect the respiratory system?

causes bronchoconstriction (tightening of airway smooth muscle) and increases mucus secretion

What are adrenergic receptors, and which ones are involved in respiratory pharmacology?

proteins that respond to epinephrine (adrenaline) and norepinephrine

Beta-2 adrenergic receptors

cause bronchodilation (main target in asthma/COPD treatment)

Alpha receptors

play a minor role (mainly in blood vessel constriction, not bronchodilation)

What type of drugs activate beta-2 adrenergic receptors, and how do they affect the lungs?

These are called beta-2 agonists (e.g., albuterol, salmeterol).

• They bind to beta-2 receptors on airway smooth muscle → cause bronchodilation → improve airflow

What is the role of muscarinic receptors in the respiratory system

mediate parasympathetic effects:

• Cause bronchoconstriction.

• Stimulate mucus secretion.

• Targeted in therapy with anticholinergic drugs to reduce airway narrowing

How do anticholinergic drugs work in respiratory care?

• Block muscarinic receptors in the lungs.

• Prevent parasympathetic-induced bronchoconstriction and mucus secretion.

• Result in bronchodilation

Sympathomimetic drug

Mimics sympathetic nervous system → stimulates adrenergic receptor

Sympatholytic drug

Blocks or reduces sympathetic activity → inhibits adrenergic receptors

What are the potential side effects of using beta-2 agonists in respiratory care?

• Tremors (most common).

• Nervousness or anxiety.

• Increased heart rate (tachycardia) or palpitations