Depolarizing agents paralyze a muscle by initially preventing its full contraction. In lay-man terms, the mechanism can be described as having the best qualifications that ensure being chosen for a work, but doing a lousy job. This prevents others from doing it any better. Technically, these agents have affinity towards the Nicotinic Ach receptor and cause depolarization at the muscle end-plate. This manifests as fasciculations that are typically observed on depolarizers’ administration. However, they prevent further binding of Ach and prevent any further contraction of the muscle, leading to flaccid paralysis (refer competitive VS depolarizing agents). Therefore, the agents are said to have sub-maximal intrinsic activity.
- These are resistant to Ach-Eases