López J R, Medina P, Alamo L
Muscle Nerve. 1987 Jan;10(1):77-9. doi: 10.1002/mus.880100114.
Malignant hyperthermia (MH) is a hereditary myopathy, triggered when susceptible patients are exposed to a depolarizing muscle relaxant and/or potent volatile anesthetics. We have studied the effects of dantrolene on the free [Ca2+]i of intercostal muscle biopsies obtained from two MH-susceptible patients before and after administration of dantrolene orally (2.5 mg/kg for 3 days) and intravenously (1.0 mg/kg 2 hours before the biopsy). The free [Ca2+]i was measured by Ca2+-selective microelectrodes. The mean resting free [Ca2+]i in the MH-susceptible muscle before dantrolene treatment was 0.42 +/- 0.01 microM (mean +/- SEM, n = 12). The administration of dantrolene reduced this value to 0.27 +/- 0.01 microM (n = 14). There was no detectable difference in the resting membrane potential after dantrolene. These results represent the first direct demonstration that dantrolene is able to reduce the resting free [Ca2+]i in skeletal muscle of MH-susceptible patients.
恶性高热（MH）是一种遗传性肌病，当易感患者接触去极化肌松药和/或强效挥发性麻醉剂时会被触发。我们研究了丹曲林对两名MH易感患者口服丹曲林（2.5mg/kg，持续3天）和静脉注射丹曲林（活检前2小时1.0mg/kg）前后肋间肌活检组织中游离[Ca2+]i的影响。游离[Ca2+]i通过Ca2+选择性微电极测量。丹曲林治疗前，MH易感肌肉中的平均静息游离[Ca2+]i为0.42±0.01微摩尔（平均值±标准误，n = 12）。丹曲林给药后，该值降至0.27±0.01微摩尔（n = 14）。丹曲林给药后静息膜电位无明显差异。这些结果首次直接证明丹曲林能够降低MH易感患者骨骼肌中的静息游离[Ca2+]i。
