Effects of prenatal exposure to low level lead on learning and memory of rats' offspring / 中华劳动卫生职业病杂志

ABSTRACT

<p><b>OBJECTIVE</b>To explore the effects of prenatal exposure to low level lead on learning and memory of rat's offspring.</p><p><b>METHODS</b>The pregnant rats were randomizedly divided into 4 groups and provided with doubly evaporated water in the control group and 125, 250 and 500 mg/L lead acetate solution via drinking water in three exposed groups respectively during the pregnancy. The learning and memory ability of 21-day old and 60-day old offsprings were tested by the Morris water maze and the shuttling and avoiding dark box respectively.</p><p><b>RESULTS</b>The blood and hippocampus lead concentrations of 1-day old and 21-day old offspring in the 3 lead-exposed groups were significantly increased compared with the control group (P < 0.05), while at the period of 60-day old there was no significant difference between them. The time to find the platform in Morris water maze for 21-day old and 60-day old offsprings of the 3 lead in the exposed groups was significantly increased compared with the control group during the 4 days training (P < 0.05). The times of initiative avoiding in the shuttling and avoiding dark box for 21-day old and 60-day old offsprings in the 3 lead-exposed groups were significantly decreased, while the latency of the initiative avoiding and latency of the passive avoiding were significantly increased compared with the control group (P < 0.05).</p><p><b>CONCLUSION</b>Prenatal exposure to low level lead impaired the space learning and memory ability of offsprings of the rats, and this kind of influence will continue till the offspring's maturity.</p>