TY - JOUR
T1 - Mitochondrial injury and caspase activation by the local anesthetic lidocaine
AU - Johnson, Michael E.
AU - Uhl, Cindy B.
AU - Spittler, Karl Heinz
AU - Wang, Hongxun
AU - Gores, Gregory J.
PY - 2004/11
Y1 - 2004/11
N2 - Background: Lidocaine, a local anesthetic, can be neurotoxic. However, the cellular mechanisms of its neurotoxicity at concentrations encountered during spinal anesthesia remain unclear. Methods: The authors examined the mechanisms of lidocaine neurotoxicity in the ND7 cell line derived from rat dorsal root ganglion. Individual neurons were assayed by flow cytometry or microscopy using fluorescent probes of plasma membrane integrity, mitochondrial membrane potential, caspase activity, phospholipid membrane asymmetry, and mitochondrial cytochrome c release. Results: In the ND7 cell line, lidocaine at 185 mM × 10 min to 2.3 mM × 24 h caused necrosis or late apoptosis. Equimolar Tris buffer and equipotent tetrodotoxin controls were not toxic, indicating that neither osmotic nor Na +-blocking effects explain lidocaine neurotoxicity. The earliest manifestation of lidocaine neurotoxicity was complete loss of mitochondrial membrane potential within 5 min after exposure to lidocaine at a concentration of 19 mM or greater. Consistent with these data, 37 mM lidocaine (1%) induced release of mitochondrial cytochrome c into the cytoplasm, as well as plasma membrane blebbing, loss of phosphatidylserine membrane asymmetry, and caspase activation, with release of mitochondrial cytochrome c to the cytoplasm within 2 h. Treatment with z-VAD-fmk, a specific inhibitor of caspases, prevented caspase activation and delayed but did not prevent neuronal death, but did not inhibit the other indicators of apoptosis. Conclusions: Collectively, these data indicate that lidocaine neurotoxicity involves mitochondrial dysfunction with activation of apoptotic pathways.
AB - Background: Lidocaine, a local anesthetic, can be neurotoxic. However, the cellular mechanisms of its neurotoxicity at concentrations encountered during spinal anesthesia remain unclear. Methods: The authors examined the mechanisms of lidocaine neurotoxicity in the ND7 cell line derived from rat dorsal root ganglion. Individual neurons were assayed by flow cytometry or microscopy using fluorescent probes of plasma membrane integrity, mitochondrial membrane potential, caspase activity, phospholipid membrane asymmetry, and mitochondrial cytochrome c release. Results: In the ND7 cell line, lidocaine at 185 mM × 10 min to 2.3 mM × 24 h caused necrosis or late apoptosis. Equimolar Tris buffer and equipotent tetrodotoxin controls were not toxic, indicating that neither osmotic nor Na +-blocking effects explain lidocaine neurotoxicity. The earliest manifestation of lidocaine neurotoxicity was complete loss of mitochondrial membrane potential within 5 min after exposure to lidocaine at a concentration of 19 mM or greater. Consistent with these data, 37 mM lidocaine (1%) induced release of mitochondrial cytochrome c into the cytoplasm, as well as plasma membrane blebbing, loss of phosphatidylserine membrane asymmetry, and caspase activation, with release of mitochondrial cytochrome c to the cytoplasm within 2 h. Treatment with z-VAD-fmk, a specific inhibitor of caspases, prevented caspase activation and delayed but did not prevent neuronal death, but did not inhibit the other indicators of apoptosis. Conclusions: Collectively, these data indicate that lidocaine neurotoxicity involves mitochondrial dysfunction with activation of apoptotic pathways.
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U2 - 10.1097/00000542-200411000-00019
DO - 10.1097/00000542-200411000-00019
M3 - Article
C2 - 15505455
AN - SCOPUS:7244234419
SN - 0003-3022
VL - 101
SP - 1184
EP - 1194
JO - Anesthesiology
JF - Anesthesiology
IS - 5
ER -