Which receptor is mutated in malignant hyperthermia?

Which receptor is mutated in malignant hyperthermia?

• A. Ryanodine receptor
• B. Acetylcholine receptor
• C. Voltage-gated sodium channel
• D. Dihydropyridine receptor

Answer: (A)

Malignant hyperthermia involves a defect in skeletal muscle calcium handling. When triggered by certain anesthetics, the mutated calcium release channel on the sarcoplasmic reticulum opens excessively, flooding the cytosol with Ca2+. That Ca2+ surge drives massive, uncontrolled muscle contraction and relentless metabolic activity, producing heat, CO2, acidosis, and potential muscle breakdown. The receptor most commonly mutated is the ryanodine receptor type 1, the SR calcium release channel. The other receptors listed are not the primary mutated players in MH: the acetylcholine receptor is linked to neuromuscular transmission disorders, the voltage-gated sodium channel to other channelopathies, and the dihydropyridine receptor participates in excitation-contraction coupling but is not the typical mutated target in malignant hyperthermia.

Malignant hyperthermia involves a defect in skeletal muscle calcium handling. When triggered by certain anesthetics, the mutated calcium release channel on the sarcoplasmic reticulum opens excessively, flooding the cytosol with Ca2+. That Ca2+ surge drives massive, uncontrolled muscle contraction and relentless metabolic activity, producing heat, CO2, acidosis, and potential muscle breakdown. The receptor most commonly mutated is the ryanodine receptor type 1, the SR calcium release channel. The other receptors listed are not the primary mutated players in MH: the acetylcholine receptor is linked to neuromuscular transmission disorders, the voltage-gated sodium channel to other channelopathies, and the dihydropyridine receptor participates in excitation-contraction coupling but is not the typical mutated target in malignant hyperthermia.