Question

Many pesticides work by inhibiting the action of acetylcholinesterase, the enzyme that normally breaks down acetylcholine within the neuromuscular junction. What effect would inhibition of acetylcholinesterase have on muscle tissue and why? What symptoms might you expect in cases of pesticide toxicity? What do you think is the most likely cause of death in these poisonings?

Answer 1

Acetylcholinesterase is found in the synapse between nerve cells and muscle cell, its main job is to breaking down the acetylcholine into its component parts, acetic acid and choline. This effectively stops the signal, allowing the pieces to be recycled and rebuilt into new neurotransmitters so that a new action potential can begin. Inhibition of acetylcholiesterase enzyme activity allows accumulation of acetylcholine, the muscle than continue to contract uncontrollably, electrical impulses can fire away continuously repeated and unchecked firing of electrical signals can cause uncontrolled, rapid twitching of some muscles, paralyzed breathing, convulsions, and in extreme cases, death.

Symptoms associated with pesticide toxcity include, headache, fatigue, dizziness, loss of appetite with nausea, stomach cramps and diarrhea;contracted pupils of the eye, excessive sweating, salvitation, In severe case it can result in  abdominal cramps, diarrhea, muscular tremors, staggering gait,abnormally low blood pressure, slow heartbeat, breathing difficulty, and possibly death, if not immediately treated.

Most often death due to pesticide poisoning is respiratory failure, it can cause  paralysis of respiratory muscles and depression of central nervous system, which is responsible for respiration.