Cholinergic Agonists · Pharmacology

What is the primary mechanism of action of organophosphate insecticides like Malathion and Parathion?

  1. Reversible inhibition of acetylcholinesterase
  2. Irreversible inhibition of acetylcholinesterase
  3. Competitive antagonism of muscarinic receptors
  4. Direct stimulation of nicotinic receptors at the ganglia
Show answer and explanation

Correct answer: Irreversible inhibition of acetylcholinesterase

Organophosphates are irreversible indirect-acting agonists. They phosphorylate the active site of acetylcholinesterase; if 'aging' occurs, the enzyme is permanently inactivated until new enzyme molecules are synthesized.

Difficulty: Medium Question 6 of 20

Practice all 20 Cholinergic Agonists questions

Keep practicing

More Cholinergic Agonists questions