[Effects of prenatal exposure to low level lead on learning and memory of rats' offspring].
OBJECTIVE
To explore the effects of prenatal exposure to low level lead on learning and memory of rat's offspring.


METHODS
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.


RESULTS
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).


CONCLUSIONS
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.
Song
Bo
B
Department of Occupational and Environmental Health, Public Health College, Hebei Medical University, Shijiazhuang, Hebei Province 050017, China.
Han
Chang-cheng
CC
Sun
Xia
X
Peng
Liang
L
Niu
Yu-jie
YJ
D000818:Animals; D004305:Dose-Response Relationship, Drug; D005260:Female; D006624:Hippocampus / Q000187:drug effects / Q000378:metabolism; D007854:Lead / Q000633:toxicity*; D018782:Maze Learning / Q000187:drug effects*; D008568:Memory / Q000187:drug effects*; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar
D007854:Lead