Effects of maternal ethanol exposure during pregnancy and lactation periods on anxiety- like behaviors and hippocampal brain-derived neurotrophic factor in rat offspring

The effects of maternal exposure to ethanol on anxiety-like behavior and hippocampal brain-derived neurotrophic factor (BDNF) expression level in the offspring are controversial. The aim of this study was to investigate the effects of maternal ethanol exposure on anxiety-like behavior and changes in BDNF levels in the hippocampus of the rats off spring.

14 pregnant Wistar rats were divided into control and ethanol groups. The rats received ethanol (4 g/kg) or distilled water on the day 0 of gestation until weaning (28 days) by oral gavage. Elevated plus maze test was performed for measurement of anxiety profile on the 35th day of postnatal period. The BDNF and TrKB receptor protein levels in the hippocampus were evaluated using ELISA kits. Data were analyzed by
independent- sample t test.

Maternal ethanol administration reduced the percentage of time spent in the open arm of the EPM and the percentage of the number of entries in the open arm significantly in the offspring compared to those in the control group (P <0.001). Also, the percentage of time spent in the closed arm and the percentage of the number of entries in the closed arm significantly increased following ethanol administration (P <0.001). In addition, ethanol treatment significantly decreased hippocampal BDNF protein levels, but did not change the TrKB receptor level in the hippocampus of the rats offspring.

Maternal ethanol exposure during pregnancy and lactation induced anxiety-like behavior and decreased hippocampal BDNF protein level in the rats offspring. Present results suggested that alteration of BDNF expression in the hippocampus of the rats exposed to ethanol during prenatal period may be involved in anxiety-like behavior