腈氯苯苯醚菊酯, 四甲菊酯及马拉硫磷对大鼠脑细胞钙振荡的毒效应机理

采用荧光探针Fura-2/Am负载技术观察了腈氯苯苯醚菊酯(Fen), 四甲菊酯(Tet)和马拉硫磷(Mal)对乳鼠脑细胞内钙振荡的影响. Fen 10～50 nmol·L^-1和Tet 20～60 nmol·L^-1具有增高胞内游离Ca²⁺浓度([Ca²⁺]_i)的作用, 但增大剂量使[Ca²⁺]_i下降. Fen可通过胞内钙, 特别是内质网(ER)的钙释放导致细胞内钙上升，胞外钙内流亦起一定作用. 在Tet的增钙作用中, 外钙内流和ER的内钙释放所占比重相近. 线粒体的钙调节作用在Fen和Tet中毒情况下未见明显变化. Fen和Mal 1∶1混用, 未见明显的联合增毒或拮抗作用.

Mechanisms underlying the toxic effects of fenvarelate, tetramethrin and malathion on calcium oscillation in rat brain cells

Using Fura-2/Am as a fluorescent probe to study fenvarelate(Fen), tetramethrin(Tet) and malathion(mal) poisoning on calcium oscillation in rat brain nerve cells. The results showed that intracellular free calcium concentrations ([Ca²⁺]_i) of neurons were increased by Fen (10-50 nmol·L^-1) and Tet (20-60 nmol·L^-1), but decreased at higher doses. The Ca⁺ release from endoplasmic reticulum was responsible to the effects of Fen on the increase of Ca²⁺, in addition, the entry of extracellular Ca²⁺ seemed to be involved. The equivalent effects of the extracellular influx and the intracellular release from endoplasmic reticulum of Ca²⁺ were observed for Tet. No effects of Fen and Tet on the regulation of mitochondria calcium were observed. Neither synergistic nor antagonistic effects of the mixture of Fen and Mal (1∶1) on calcium oscillation were detected.