Cytotoxic effects of procaine, lignocaine and bupivacaine.

Cytotoxic effects of procaine, lignocaine and bupivacaine were investigated on cultures of Chinese hamster lung fibroblasts. Cell growth was inhibited over 24 h exposures with an ED50 of 0.17% for procaine, 0.07% for lignocaine and 0.02% for bupivacaine. Cell survival (measured as colony-forming ability) was reduced over 24 h exposure with an ED50 of 0.21% for procaine, 0.09% for lignocaine and 0.06% for bupivacaine. Morphological changes included vacuolation, cell rounding and retraction from the surface on which the cells were growing. Motility was reduced to about 50% of control by lignocaine 0.1%. On removal of the local anaesthetics, cell growth was resumed after about 15 h without evidence of chromosome damage. Corresponding changes induced by inhalation anaesthetics are only seen at two to three times the minimal alveolar concentration required for anaesthesia.