Open AccessIs Resting Membrane Potential a Possible Indicator of Viability of Muscle Bundles Used in the In Vitro Caffeine Contracture Test?
Author(s) -
P. Adnet,
Ren e M. Krivosic-Horber,
M. M. Adamantidis,
G. Haudecœur,
H. Reyford,
B Dupuis
Publication year - 1992
Publication title -
anesthesia and analgesia/anesthesia and analgesia
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.404
H-Index - 201
eISSN - 1526-7598
pISSN - 0003-2999
DOI - 10.1213/00000539-199201000-00017
Subject(s) - caffeine , malignant hyperthermia , contracture , medicine , depolarization , muscle biopsy , hyperthermia , anesthesia , membrane potential , skeletal muscle , biopsy , surgery , biophysics , biology
In 22 patients susceptible to and 34 patients not susceptible to malignant hyperthermia, we examined which muscle conditions may influence the degree of sensitivity of skeletal muscle to the in vitro caffeine contracture test: predrug resting membrane potential, predrug twitch tension, and maximum contracture induced by 32 mM caffeine in two caffeine tests performed respectively at 30 and 75 min after biopsy. No differences in the measured variables were observed between the first and the second caffeine tests in the 34 patients susceptible to malignant hyperthermia. The first caffeine test was found to be positive in all of the 22 patients susceptible to malignant hyperthermia. However, in eight patients, the second caffeine test was negative and the muscle fibers were found to be significantly depolarized. Resting membrane potential was -73.4 +/- 7.9 mV before the first caffeine test and -65.8 +/- 8.8 mV before the second test. We suggest that when time-induced partial depolarization of malignant hyperthermia-susceptible fibers occurs, fibers may become less sensitive to caffeine.