The membrane potential of Chinese hamster fibroblasts was determined to be (-29,9 ± 6.5) mV. Fibroblast membranes irradiated with red laser light of 670 nm were partially depolarized. This effect was observed for energy doses of 5 J and 10 J. The energy dose of 15 J did not further decrease the membrane potential. In contrast to the red light, the irradiation with green laser light (543.5 nm) did not change fibroblast membrane potential.
Malignant hyperthermia (MH) is a clinical syndrome in which genetically susceptible individuals respond to the administration of potent inhalation anaesthetics and depolarization skeletal muscle relaxants with skeletal rigidity, unstable blood pressure, tachycardia, arrhythmias, hyperventilation, hypoxia, lactic and respiratory acidosis and high fever. In studies of the genetic basis of MH, a mutation was identified in the porcine (C1843T) and human (C1840T) skeletal muscle ryanodine receptor (RYR1) gene. This gene is mapped on human chromosome 19q13.1. The RYR1 gene contains 106 exons, of which two arc alternatively spliced.