LEUKOCYTE HYDROGEN-PEROXIDE PRODUCTION IN A SURGICAL-WOUND IN MICE - THE EFFECTS OF AN AMIDE LOCAL-ANESTHETIC

The oxygen metabolism of polymorphonuclear leukocytes (PMN) is of impo rtance in local tissue repair processes. Amide local anaesthetics are commonly used to relieve surgical wound pain. The cellular effects of local anaesthetics in vivo is poorly described in the literature. Howe ver, interactions between amide local anaesthetics and the oxygen meta bolism of leukocytes have been reported. To extend that knowledge, thi s paper investigates the influence of lidocaine treatment on the produ ction of hydrogen peroxide (H2O2) by leukocyte oxygen metabolism. A so ft tissue chamber model in the mouse was used, allowing measurements o f the H2O2 production spontaneously and after phorbol myristate acetat e (PMA) addition, from two different leukocyte pools. Exudate leukocyt es were generally more reactive to PMA stimulation in comparison to ti ssue chamber adherent leukocytes. Topically administered lidocaine sig nificantly influenced the number of leukocytes in the wound exudate at 24 h postoperatively. Exudate leukocytes, topically exposed to lidoca ine, showed an enhanced H2O2 production in comparison to leukocytes re ceiving lidocaine systemically. At 6 days, the viability and the H2O2 production differed significantly between the group receiving topicall y applied lidocaine in comparison to placebo. We conclude that the wou nd healing process may be effected by topically applied lidocaine, adm inistered in clinical doses, at least via interference with leukocyte oxygen metabolism.