ABSTRACT
<p><b>OBJECTIVE</b>To investigate the effects of benzo[a]pyrene (B[a]P) exposure on the behaviors and hippocampal oxidative stress and ATPase in rats and the molecular mechanism of neurobehavioral toxicity of B[a]P.</p><p><b>METHODS</b>A total of 120 male SD rats (21 days old) were randomly and equally assigned to five groups: blank control group, vegetable oil (solvent control) group, and 2.5, 5, and 10 mg/kg B[a]P exposure groups. The rats in B[a]P exposure groups were injected intraperitoneally with B[a]P once a day for 4 consecutive weeks. Then, Morris water maze and shuttle box were used to evaluate the learning and memory abilities of rats; colorimetric assay was used to measure the activities of superoxide dismutase (SOD), Na(+)/K(+)-ATPase, and Ca(2+)/Mg(2+)-ATPase and the content of malonaldehyde (MDA) in the hippocampus; the concentration of Ca(2+) in the hippocampus was measured by fluorescent labeling.</p><p><b>RESULTS</b>Compared with the blank control group and solvent control group, the B[a]P exposure groups exhibited significant increases in escape latency, active avoidance response latency, and passive avoidance response latency and significant decreases in number of platform crossings and active avoidance response frequency in the last test (P < 0.05 for all comparisons), with a dose-effect relationship. In addition, the B[a]P exposure groups had significantly lower activities of SOD, Na(+)/K(+)-AT-Pase, and Ca(2+)/Mg(2+)-ATPase and significantly higher MDA level and Ca(2+) concentration than the blank control group and solvent control group (P < 0.05 for all comparisons), with a dose-effect relationship.</p><p><b>CONCLUSION</b>The neurobehavioral toxicity of B[a]P may be related to increased oxidative stress and decreased activities of Na(+)/K(+)-ATPase and Ca(2+)/Mg(2+)-ATPase in the hippocampus of rats.</p>
Subject(s)
Animals , Male , Rats , Benzo(a)pyrene , Toxicity , Ca(2+) Mg(2+)-ATPase , Metabolism , Hippocampus , Metabolism , Oxidative Stress , Rats, Sprague-Dawley , Sodium-Potassium-Exchanging ATPase , Metabolism , Superoxide Dismutase , MetabolismABSTRACT
ObjectiveTo study an application of a method of improving the quality of sampling in review to determine the light areas of endemic fluorosis(referred to as endemic fluorosis) in quality control. Methods Of 15 light endemic fluorosis township(town), six were randomly sampled, and the prevalence of dental fluorosis in 22 village primary school children aged 8 to 12 were reviewed to determine the improved quality of sampling in Xuyong county Sichuan province. ResultsSix townships(towns) were selected by simple random sampling from 15 endemic fluorosis townships(towns) for review inspection in Xuyong country. A total of 22 villages were verified, accounting for 22.7％ of the total 97 villages verified. Of the 416 children for review inspection of dental fluorosis, 383 children were positive. The consistent rate of children' s dental fluorosis was 92.07％, and the verification to be slight villages was up to 21 endemic villages, accounting for 95.45％. ConclusionsThe application of a method of improving the quality of sampling can improve the efficiency of quality control, and improve the accuracy. It is a novel quality control method.