Which receptor is activated by OC spray components leading to irritation?

• A. NMDA receptors
• B. TRPV1 receptors
• C. GABA receptors
• D. TRPM8 receptors

Answer: (B)

OC spray irritants, especially capsaicinoids like capsaicin, stimulate TRPV1 receptors—the vanilloid receptors—on sensory nerve endings. When these receptors are activated, they open ion channels that let calcium and sodium into the cell, triggering pain signals and causing burning, tearing, coughing, and a stinging sensation. This is why OC spray feels intensely irritating to the eyes and mucous membranes. The other receptors listed aren’t the primary targets for these components: NMDA receptors are central nervous system glutamate receptors involved in synaptic plasticity and pain processing but aren’t directly activated by capsaicinoids; GABA receptors mediate inhibition in the CNS; TRPM8 receptors respond to cold and menthol rather than the irritant effects of capsaicinoids.