The exposure to nicotine affects expression of brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) in neonate rats

In the current study effect of nicotine on expression of neurotrophins, brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) has been studied in hippocampus and frontal cortex during development of brain in rats. Neurotrophins are factors that help in development of brain among which BDNF and NGF are very important, expressed at different stages during the developmental process. Different sedatives are reported to alter the expression of these factors. In this study, three groups of neonate rats (1-5, 5-10 and 10-15 days age) were used each having 20 rats. Ten were subjected to a dose of 66 mu g of nicotine while other ten received the same amount of saline at the same time interval. Then expression of the BDNF and NGF was observed in hippocampus and frontal cortex tissue using immunoassay. Western blotting was used to observe the presence of BDNF in hippocampus as well as frontal cortex. In all groups there was a significant decrease in concentration of neurotrophic factors where nicotine was applied as compared to control. The highest expression of BDNF and NGF in hippocampus and frontal cortex was observed in 10-15 days group (G3) and in 5-10 group (G2) as compared to the control, P < 0.01. It was concluded that exposure of neonate rats to nicotine causes a decrease in the expression of NGF and BDNF and it effects the development of brain in neonates that can further impair brain functions.