Question

Diazinon is an insecticide, which acts through inhibition of acetylcholinesterase. Which of the following would you expect to be diazinon's immediate impact at the skeletal neuromuscular junction?

A) Variable effect on muscular contraction
B) Decreased muscular contraction
C) Increased muscular contraction
D) Diazinon should have no effect at the neuromuscular junction

Answer 1

The immediate impact of diazinon at the neuromuscular junction is increased muscular contraction due to the inhibition of acetylcholinesterase and the resulting accumulation of acetylcholine.

Step-by-step explanation:

Diazinon is an insecticide which acts by inhibiting acetylcholinesterase, an enzyme that breaks down the neurotransmitter acetylcholine. This inhibition would lead to an accumulation of acetylcholine at the synaptic cleft of a neuromuscular junction. As a result, you would expect the immediate impact of diazinon at the skeletal neuromuscular junction to be C) Increased muscular contraction. The continuous stimulation by acetylcholine would cause the muscle to keep contracting without relaxation, potentially leading to muscle fatigue and paralysis if not treated.