Evaluation of genotoxicity induced by repetitive administration of local anaesthetics: an experimental study in rats

Background and objective: Previous studies regarding the effects of some local anaesthetics have suggested that these agents can cause genetic damage. However, they have not been tested for genotoxicity related to repetitive administration. The aim of this study was to evaluate the genotoxic potential of local anaesthetics upon repetitive administration. Methods: 80 male Wistar rats were divided into: group A – 16 rats intraperitoneally injected with lidocaine hydrochloride 2%; group B – 16 rats IP injected with mepivacaine 2%; group C – 16 rats intraperitoneally injected with articaine 4%; group D – 16 rats IP injected with prilocaine 3% (6.0 mg/kg); group E – 8 rats subcutaneously injected with a single dose of cyclophosphamide; and group F – 8 rats intraperitoneally injected with saline. Eight rats from groups A to D received a single dose of anaesthetic on Day 1 of the experiment; the remaining rats were dosed once a day for 5 days. Results: The median number of micronuclei in the local anaesthetics groups exposed for 1 or 5 days ranged from 0.00 to 1.00, in the cyclophosphamide-exposed group was 10.00, and the negative control group for 1 and 5 days was 1.00 and 0.00, respectively (p 0.05). Conclusion: No genotoxicity effect was observed upon repetitive exposure to any of the local anaesthetics evaluated. Resumo: Justificativa e objetivos: Estudos anteriores sobre os efeitos de alguns anestésicos locais sugeriram que esses agentes podem causar alterações genéticas. No entanto, esses agentes não são testados para genotoxicidade relacionada à administração repetida. O objetivo deste estudo foi avaliar o potencial genotóxico de anestésicos locais após repetidas administrações. Métodos: 80 ratos Wistar machos foram alocados em: grupo A – 16 ratos receberam injeção por via intraperitoneal (IP) de cloridrato de lidocaína a 2%; grupo B – 16 ratos receberam injeção IP com mepivacaína a 2%; grupo C – 16 ratos receberam injeção IP de articaína a 4%; grupo D – 16 ratos receberam injeção IP de prilocaína a 3% (6,0 mg kg−1); grupo E – 8 ratos receberam injeção subcutânea em dose única de ciclofosfamida; grupo F – 8 ratos receberam injeção IP com solução salina. Oito ratos dos grupos de A a D receberam uma dose única de anestési