Ganglionic Blockers/Neuromuscular Blockers

These flashcards cover key terms and definitions related to ganglionic blockers and neuromuscular blockers as discussed in the lecture notes.

Neuromuscular blockers

Drugs that act at nicotinic acetylcholine receptors at the neuromuscular junction, producing muscle paralysis and promoting muscle relaxation.

Nicotinic acetylcholine receptors

Receptors that, when activated by acetylcholine, cause muscle contraction at the neuromuscular junction.

Depolarizing neuromuscular blockers

A class of neuromuscular blockers, such as succinylcholine, that cause persistent depolarization of the motor end plate, leading to muscle relaxation.

Non-depolarizing neuromuscular blockers

A class of neuromuscular blockers that compete with acetylcholine for binding to nicotinic receptors without causing depolarization.

Action potential

An electrical impulse that transmits along the motor neuron, causing the release of acetylcholine at the neuromuscular junction.

Acetylcholine (ACh)

A neurotransmitter released at the neuromuscular junction that binds to nicotinic receptors to induce muscle contraction.

Phase I depolarizing block

A phenomenon where, due to excessive stimulation at the motor end plate, muscle tone becomes flaccidly paralyzed without repolarization occurring.

Phase II depolarizing block

A condition following continued exposure to succinylcholine where nicotinic receptors become desensitized and lead to muscle paralysis despite some repolarization.

Acetylcholinesterase (AChE)

An enzyme that rapidly breaks down acetylcholine in the synaptic cleft, regulating the effects of acetylcholine.

Spasmolytic drugs

Drugs used to relieve muscle spasms and stiffness in conditions like spasticity, acting via various mechanisms, often centrally.

Baclofen

A spasmolytic drug that is a GABAB receptor agonist, typically used to treat muscle spasms caused by multiple sclerosis or spinal lesions.

Tizanidine

An α2 agonist that reduces spasticity by increasing presynaptic inhibition of motor neurons, structurally related to clonidine.

Dantrolene

A direct acting muscle relaxant that reduces spasticity by blocking calcium release from the sarcoplasmic reticulum.

Riluzole

A neuroprotective agent used in ALS that acts as a glutamate antagonist to reduce excitotoxicity.

Succinylcholine

A depolarizing neuromuscular blocker used clinically to produce muscle relaxation during intubation, characterized by a rapid onset and brief duration.

Atracurium

A non-depolarizing neuromuscular blocker that is metabolized by hydrolysis, useful in patients with hepatic or renal issues.

d-Tubocurarine

A non-depolarizing neuromuscular blocker that can induce histamine release and has a longer duration of action compared to some newer agents.

Rocuronium

An intermediate-acting non-depolarizing neuromuscular blocker known for its rapid onset and lack of significant histamine release.