Calcium-induced Ca2+ release from sarcoplasmic reticulum of pigs susceptible to malignant hyperthermia. The effects of halothane and dantrolene.

Calcium-induced calcium release and halothane-induced calcium release from pig sarcoplasmic reticulum (SR) were studied. The SR prepared from pigs susceptible to malignant hyperthermia (MH) was shown to release calcium at a much lower level of calcium content than in normal pig SR. The concentration above which halothane can release calcium is 40 microM for both MH-SR and normal SR, although the latter required a high calcium content to demonstrate the calcium release. Dantrolene was shown to inhibit the halothane-induced calcium release. Results suggest that SR plays an important role in pathogenesis of MH.