PNAS resolves the molecular mechanism of exercise-induced heatstroke: thermosensitive calcium channels

Hot summer days may have you reaching for a fan and an iced drink to keep you co.

In a new study, a research team led by Osaka University has revealed that malignant hyperthermia (MH) is caused by heat-allergic mutant calcium channel protei.

MH is a condition in which body temperature rises uncontrollably after anesthes.

To investigate this, the researchers used an infrared laser beam to precisely heat cultured cells expressing the mutant RyR1 protein and assessed changes in calcium flux using fluorescent calcium imagi.

"The results were very clear," said Madoka Suzuki, the study's senior auth.

Importantly, the release of calcium into the intracellular milieu in response to heat via the HICR mechanism may further accelerate cellular thermogenesis, resulting in a cascading effe.

"Our findings suggest that when calcium leakage through RyR1 mutant channels is enhanced by MH-inducing agents, such as anesthetics, a positive feedback loop is created, leading to the release of more and more calci.

Given that recent studies have shown a strong relationship between malignant hyperthermia and heatstroke, the findings of this study could also provide clues to understanding how exercise-induced heatstroke occurs under extreme environmental conditio.

article title

Heat-hypersensitive mutants of ryanodine receptor type 1 revealed by microscopic heating