Epidural clonidine causes an increase in T-helper1 lymphocytes and a decrease in T-helper2 lymphocytes in patients undergoing lung surgery

Abstract

Recently, we have shown that bupivacaine and ropivacaine enantiomers stereoselectively alter Ca 2ϩ homeostasis in striated myocytes. 2 Examining the racemates of pipecoloxylidide local anaesthetics, it was the aim of this study to investigate the impact of lipophilicity on Ca 2ϩ regulation in muscle fibres. Materials and Methods: Bupivacaine, ropivacaine and mepivacaine racemates were tested in concentrations of 5, 10 and 15 mM. Saponin skinned murine skeletal muscle fibers were loaded at 0.41 M Ca 2ϩ according to a standardised protocol. 1,2 To assess the effects on Ca 2ϩ uptake, agents were added to the 'loading solution', and caffeine induced force transients were measured. Further-more, agents were added to the release solution to investigate the effects on Ca 2ϩ release from the sarcoplasmic reticulum. Force transients were normalised to maximum force at 24.9 M Ca 2ϩ , and mathematically transferred into Ca 2ϩ transients (5 fibres per agent and concentration; statistics: One-way analysis of variance/t-test). Results: Data (mean Ϯ SD; in M) are shown in the Table.