ABSTRACT
<p><b>OBJECTIVE</b>To observe the effect of chronic lead contaminant on mRNA expression of protein kinase C (PKC) and calmodulin (CaM) in hippocampus of baby rats.</p><p><b>METHODS</b>The Wistar pregnant rats were randomly divided into 3 groups fed with distilled water and lead contained water (0.2% and 1.0% lead acetate) respectively. The lead exposure period was from the 0 day of pregnancy to the day when the offspring weaned. Then the baby rats were fed with lead water the same as their mothers. The cliff avoidance reflex within postnatal day 8 and step down test at postnatal day 50 were performed. Then pups were killed at postnatal day 8 and 50 respectively. Atomic absorption spectrometry was used to determine lead content of rats' brain. RT-PCR was used to observe mRNA expression of PKC and CaM in hippocampus of baby rats.</p><p><b>RESULTS</b>The brain lead content of test groups were much higher than that of the control group. The completion rate of cliff avoidance reflex and the score of step down test of test groups were lower than those in the control group (P < 0.05). Compared with control group, PKC and CaM mRNA expression of chronic lead exposure baby rats in the hippocampus had the down trend (P < 0.05).</p><p><b>CONCLUSION</b>The decrease of PKC and CaM mRNA expression level in hippocampus has a great link with the impairment of learning and memory induced by lead in baby rats, which might be one of the molecule mechanisms of lead induced impairment of learning and memory.</p>
Subject(s)
Animals , Female , Male , Rats , Calmodulin , Genetics , Metabolism , Hippocampus , Metabolism , Lead , Toxicity , Learning , Memory , Protein Kinase C , Genetics , Metabolism , RNA, Messenger , GeneticsABSTRACT
<p><b>OBJECTIVE</b>To observe the effects of chronic lead exposure on mRNA and protein expression of ASIC1a, ASIC2a, ASIC2b in hippocampus of baby-rats.</p><p><b>METHODS</b>The Wistar pregnant rats were randomly divided into 3 groups fed with distilled water or lead contained water (0.2% and 1.0% lead acetate) respectively, 5 rats in each group. The lead-exposure ranged from the 0 day of pregnancy to the offspring weaned. Then the baby-rats were fed with lead water like their mothers and killed at postnatal day 8 or 50. Atomic absorption spectrometry was used to determine lead content in the brain. RT-PCR and Western blotting were used to observe mRNA and protein expression of ASIC1a, ASIC2a and ASIC2b in their hippocampus respectively.</p><p><b>RESULTS</b>The brain lead content of test groups was higher than that of the control group (P < 0.01), and the lead content of the postnatal day 50 was higher than that in postnatal day 8 (P < 0.01). Compared with the control group, ASIC1a mRNA expression of 1.0% lead exposure in the hippocampus was uptrend (P < 0.01), ASIC1a protein expression of each test group was downtrend (P < 0.05), while for ASIC2a and ASIC2b mRNA and protein, there was no significant differences observed (P > 0.05).</p><p><b>CONCLUSION</b>ASIC1a expression in hippocampus can be changed by chronic lead exposure.</p>