Effect of gestational and lactational exposure to the polychlorinated biphenyl mixture aroclor 1254 on learning and memory and hippocampus in rat offspring / 中华行为医学与脑科学杂志

ABSTRACT

Objective To explore the effect of polychlorinated biphenyls (PCBs) on the learning and memory of gestational and lactational exposure to polychlorinated biphenyls in rats offspring.Methods The PCB mixture (A1254,0,5,10,20 mg/kg body weight) was administered to pregnant wistar rats every 3 days by gavage from gestational day (GD) 5 to postnatal day (PND) 20.To assess the effects on offspring following such exposure,Morris water maze test was performed to assess the learning and memory ability.Calcium concentration was assayed in hippocampus and the ultramicro structure was observed.Results After training for four days,the escaping latency in every group decreased significantly compared with the first day,especially the control group,the results in the fourth day decreased significantly with the early three days(P＜0.05).The offsprings of the 10 and 20 mg/kg had prolonged time of passing the aim target ((5.23± 1.16) s,(7.90±3.21) s,(11.74±6.56) s and (20.83± 8.38) s ; P＜0.05),decreased number of crossing platform ((4.14± 1.21),(3.00± 1.32),(2.65± 1.13),(2.42± 1.31) ; P＜0.05) and swimming time in the target area ((40.14±7.14)s,(33.76±5.58)s,(32.45±6.00)s and (30.63±5.10) s; P＜0.05)compared with those of the rats of control and 5 mg/kg groups.The calcium concentration increased ((121.16± 12.23) nM,(141.27±24.66) nM,(163.32±29.75) nM,(261.46±27.79) nM) and the ultramicro structure in hippocampus changed obviously in the high exposure group.Conclusion Gestational and lactational exposure to aroclor 1254 in rats could affect the leaming and memory ability of offsprings.