Influence of maternal nicotine exposure on neonatal rat bone: protective effect of ascorbic acid.

Limited research in young adults and immature animals suggests a detrimental effect of tobacco on bone during growth. We aimed to determine the adverse effects of maternal nicotine exposure during pregnancy and lactation on neonatal rat bone development, and to determine a protective effect of ascorbic acid. Gravid rats were assigned into three groups: two experimental and one control (group I). In the first experimental group (group II), pregnant rats received 3 mg/kg/d nicotine subcutaneously during pregnancy from 1 to 21 days of gestation and lactation (until postnatal day 21). The second experimental group (group III) received nicotine and ascorbic acid (1 mg/kg body mass/d). Whole body mineral density (BMD), content (BMC), and area (BA) were measured on postnatal day 21. Histopathologic and morphologic findings of the femur were obtained. Maternal nicotine exposure decreased the body weight of the rat at the birth and postnatal day 21. The values of BMD, BA, and BMC of the groups were similar to each other. Width of the epiphyseal plate and the hypertrophic zone were higher in group III but lower in group II than in group I. Number of apoptotic chondrocytes was significantly increased in group II. The length of femur was higher in group I but lower in group II than in group III. Maternal nicotine exposure during gestation and lactation resulted in decreased body weight and bone lengthening. Ascorbic acid supplementation was found to prevent the adverse effects of maternal nicotine exposure on the growth plate.