Research On The In Vitro Efects Of Three Daily Used Local Anesthetics Agents-Lidocaine, Ropivacaine And Bupivacaine On The NK Cell Cytotoxicity

Background: Natural killer (NK) cells constitute an essential component of the innate immune system in the defence against infected and malignant cells. In this study the in vitro effects on NK cell activity of three different local anesthetics was investigated.Objective: The present study was to investigate the in vitro effect of three amide local anesthetic agents, lidocaine, ropivacaine and bupivacaine, on the NK cell cytotoxicity. We hypothesized that the estimated in vitro NK cell cytotoxicity and the concentration of the three tested local anesthetic agents was negatively associated.Methods: Venous blood from seven healthy volunteers was collected. mononuclear cells were isolated. PBMC incubated with three amide local anesthetics with two different concentrations: lidocaine 0.50 mg/ml, and 2.00 mg/ml, ropivacaine 0.375 mg/ml, and 1.50 mg/ml, and bupivacaine 0.25 mg/ml, and 1.00 mg/ml. After 1 h of incubation, PBMC were for NK cell cytotoxicity in a 4-h release assay against K-562 target cells. Natural killer cell cytotoxicity of mononuclear cells incubated with isotonic saline was used as the control.Results: A significant suppression in NK cell cytotoxicity was demonstrated for all three local anesthetic agents when the NK cell cytotoxicity was compared with the cytotoxicity estimated after incubation with isotonic saline (P<0.05). Moreover a significant overall concentration-dependent effect (P<0.05) on the NK cell cytotoxicity was found.Conclusion: The results of the present in vitro study suggest a negative association between the estimated NK cell cytotoxicity and the concentrations of the three local anesthetic agents tested.