Malformações congênitas de embriões de camundongas expostas ao álcool e à nicotinamida Congenital malformations in embryos of female mice exposed to alcohol and nicotinamide

Objective: To compare the incidence of congenital malformations among the offspring of female mice exposed to alcohol or alcohol plus nicotinamide. Methods: Three groups of pregnant C57BL/6J mice were studied; G1 received alcohol (5 g/kg) in saline solution (20% - vol/vol); G2 received nicotinamide, 50 mg/ml associated to alcohol; and G3, only saline solution; all by intraperitoneal injection on the seventh day of pregnancy. The animals were killed in a CO 2 chamber on day 18 of pregnancy. The intrauterine content was assessed and the number of complete and reabsorbed fetuses was counted. The complete fetuses had their weight and crown-rump length measured and malformations were identified. Results: G1 showed the highest number of malformations: micrognathia, low set ears, hypertrophic nose, scoliosis, and atrophy of the lower and upper limbs. Weight was significantly different among the groups (p = 0.0139), and in G1 it was below average as compared to G3 (p = 0.3133). As for length, the lowest values were found in G2 and G3 showed the highest ones. There was a significant difference among the groups (p = 0.0145). Conclusions : Ethanol, when administered to pregnant mice was teratogenic. However, length of G1 fetuses was, in average, higher than that of other groups. Nicotinamide decreased the number of malformations and may be a possible protector against alcohol effects.