Heavy metal toxicity and differential effects on the hyperglycemic stress response in the shrimp Palaemon elegans
Heavy metal toxicity and differential effects on the hyperglycemic stress response in the shrimp Palaemon elegans
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DOI：
10.1007/s002440010093
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发表时间：
2000-08-01
影响因子：
4
通讯作者：
Ferrero, EA
中科院分区：
文献类型：
--
作者：
Lorenzon, S;Francese, M;Ferrero, EA
农业和工业活动造成水生环境重金属污染。甲壳类动物对重金属的敏感性已有充分记录。然而，受亚致死毒性和应激反应影响的生理功能的激素和代谢目标却很少被研究。将秀丽隐杆线虫暴露于人造海水中溶解浓度不断增加的重金属中，在完整无眼柄动物中进行 96 小时的 LC50 测试，结果显示毒性顺序为汞，其中汞的毒性最强，其次是镉、铜、锌和铅。人们发现，无眼柄的动物比完整的个体更敏感。重金属会影响血糖水平，但操作性压力则不会。 Hg、Cd 和 Pb 的中间亚致死浓度在 3 小时内产生显着的高血糖反应，而最高浓度在 24 小时内不引起高血糖。相比之下，暴露于铜和锌的动物即使在高浓度下也表现出高血糖。 Cu 或 Zn 与非必需重金属 Cd、Hg 或 Pb 之间的反应差异可能可以通过前者在甲壳类动物中的生理作用和耐受性适应来解释。通过对无眼柄个体进行常规生物测定来测试甲壳动物高血糖激素（cHH）的参与情况；每组都注射了来自对照动物或暴露于高浓度镉、汞、铅或低浓度铜或锌的虾的两眼柄当量提取物。所有患者均在 2 小时内出现高血糖反应。相比之下，从暴露于低浓度的汞、镉、铅或高浓度的铜和锌后发生完全高血糖反应的动物身上取出的眼柄提取物中的cHH被耗尽，如将提取物注射到无眼柄动物中后反应减弱所表明的那样。这种普遍且可预测的亚致死反应可用作水质监测评估的定量生理生物标志物。
Agricultural and industrial activities cause heavy metal pollution of the aquatic environment. The sensitivity of crustaceans to heavy metals is well documented. However, the hormonal and metabolic target of physiological functions affected by sublethal toxicity and stress responses have been scarcely investigated. Exposure of Palaemon elegans to increasing concentrations of heavy metals dissolved in artificial sea water resulted in an order of toxicity tested by LC50 for 96 h in intact and eyestalkless animals in which Hg is the most toxic, followed by Cd, Cu, Zn, and Pb. Eyestalkless animals were found to be more sensitive than intact individuals. Heavy metals affect the blood glucose levels, yet manipulative stress does not. The intermediate sublethal concentrations of Hg, Cd, and Pb produced significant hyperglycemic responses within 3 h, while the highest concentrations elicited no hyperglycemia in 24 h. In contrast, animals exposed to Cu and Zn showed hyperglycemia even at high concentrations. This difference in response between Cu or Zn and the nonessential heavy metals Cd, Hg, or Pb can probably be explained by the physiological roles of the former in crustaceans and by tolerance adaptations. Involvement of the crustacean hyperglycemic hormone (cHH) was tested by routine bioassay on eyestalkless individuals; each group was injected with a two-eyestalk-equivalent extract from control animals or from shrimp exposed to high concentrations of Cd, Hg, Pb, or low concentrations of Cu or Zn. All showed a hyperglycemic response within 2 h. In contrast, extracts of eyestalk removed from animals that had developed a full hyperglycemic reaction after exposure to low concentrations of Hg, Cd, Pb, or high concentrations of Cu and Zn were depleted of cHH as shown by the attenuation of the response after injection of the extracts into eyestalkless animals. This generalized and predictable sublethal response can be used as a quantitative physiological biomarker for water quality monitoring assessment.