Lidocaine-induced apoptosis of gingival fibroblasts: participation of cAMP and PKC activity.
Local anaesthetics are drugs that prevent or relieve pain by interrupting nervous conduction and are the most commonly used drugs in dentistry. Their main targets of action are voltage-dependent Na+ channels. The Na+ channel is modulated by phosphorylation of two enzymes: PKA (protein kinase A) and PKC (protein kinase C). We studied the ability of lidocaine to modulate programmed cell death of human gingival fibroblasts and the mechanisms involved in this process. Lidocaine (10-5 to 10-7 M) stimulated apoptosis in primary cultures and the caspase-3 activity in a concentration-dependent manner. The stimulatory effect of lidocaine on apoptosis was attenuated in the presence of HA 1004 (PKA inhibitor) and stimulated by staurosporine and Go 6976 (PKC inhibitors). Lidocaine-induced apoptotic nuclei correlated positively with cAMP accumulation and negatively with PKC activity. These results show that lidocaine promotes apoptosis in human gingival fibroblasts at concentrations used for local anaesthesia. The mechanism involves PKA stimulation and PKC inhibition, which in turn stimulates caspase-3 and leads to programmed cell death.
Pharmacology Unit, School of Dentistry, University of Buenos Aires, Buenos Aires, Argentina.
Emmanuel Quinteros
EQ
Villarruel
Enri
E
Borda
Leonor
L
Sterin-Borda
Betina
B
Orman
D017209:Apoptosis / Q000187:drug effects*; D002227:Carbazoles; D053148:Caspase 3 / Q000378:metabolism; D002478:Cells, Cultured; D000242:Cyclic AMP / Q000378:metabolism*; D017868:Cyclic AMP-Dependent Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D005347:Fibroblasts / Q000378:metabolism; D005881:Gingiva / Q000187:drug effects* / Q000378:metabolism; D006801:Humans; D020287:In Situ Nick-End Labeling; D007546:Isoquinolines / Q000494:pharmacology; D008012:Lidocaine / Q000494:pharmacology*; D011493:Protein Kinase C / Q000037:antagonists & inhibitors / Q000378:metabolism*; D047428:Protein Kinase Inhibitors / Q000494:pharmacology; D019311:Staurosporine / Q000494:pharmacology; D013449:Sulfonamides / Q000494:pharmacology
D002227:Carbazoles; D007546:Isoquinolines; D047428:Protein Kinase Inhibitors; D013449:Sulfonamides; C081021:Go 6976; C043204:N-(2-guanidinoethyl)-5-isoquinolinesulfonamide; D008012:Lidocaine; D000242:Cyclic AMP; D017868:Cyclic AMP-Dependent Protein Kinases; D011493:Protein Kinase C; D053148:Caspase 3; D019311:Staurosporine