Local anesthetics enhance nitric oxide production by human peripheral neutrophils.

Various neutrophil functions are suppressed by local anesthetics. We studied the effect of local anesthetics on nitric oxide (NO) generation in human peripheral neutrophils. Lidocaine and other local anesthetics stimulated NO generation in resting neutrophils. Canavanine, an NO synthase inhibitor, inhibited NO generation. Lidocaine and the other local anesthetics enhanced formylmethionyl-leucyl-phenylalanine (FMLP) or phorbol myristate acetate (PMA)-induced NO generation. These findings suggest that NO mediates various pharmacological effects of the local anesthetics on the host defense mechanism and the control of blood pressure.