Inhibitory effect of lidocaine on the sarcoplasmic reticulum Ca2+-dependent atpase from temporalis muscle.

Abstract

Myotoxic effects of local anesthetics on skeletal musclefibers involve the inhibition ofsarcoplasmic reticulum Ca2+ -dependent ATPase activity and Ca2 transport. Lidocaine is a local anesthetic frequently used to relieve the symptoms of trigeminal neuralgia. The aim of this work was to test the inhibitory and/or stimulatory effect of lidocaine on sarcoplasmic reticulum Ca2+ -dependent ATPase isolated from rabbit temporalis muscle. Ca2+ -dependent ATPase activity was determined by a colorimetric method Calcium-binding to the Ca dependent ATPase, Ca2+ transport, and phosphorylation of the enzyme by ATP were determined with radioisotopic techniques. Lidocaine inhibited the Ca2+ -dependent ATPase activity in a concentration-dependent manner. The preincubation of the sarcoplasmic reticulum membranes with lidocaine enhanced the Ca2+ dependent ATPase activity in the absence of calcium ionophore. Lidocaine also inhibited both Ca2+ uptake and enzyme phosphorylation by ATP but had no effect on Ca2+ -binding to the enzyme. We conclude that the effect of lidocaine on the sarcoplasmic reticulum Ca2+ -dependent ATPase from temporalis muscle is due to the drug's direct interaction with the enzyme and the increased permeability of the sarcoplasmic reticulum membrane to Ca.

• Authors: Gabriel A Sánchez, Ana C Casadoumecq, Guillermo L Alonso, Delia Takara
• Journal: Acta odontologica latinoamericana : AOL (Acta Odontol Latinoam) Vol. 23 Issue 2 Pg. 92-8 ( 2010) ISSN: 0326-4815 [Print] Argentina
• PMID: 21053680 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Anesthetics, Local
• Lidocaine
• Sarcoplasmic Reticulum Calcium-Transporting ATPases

Topics

• Anesthetics, Local (pharmacology)
• Animals
• Lidocaine (pharmacology)
• Male
• Rabbits
• Sarcoplasmic Reticulum Calcium-Transporting ATPases (antagonists & inhibitors)
• Temporal Muscle (enzymology)