Luedeking Alexander, Koehler Angela
Biologische Anstalt Helgoland in the Foundation of the Alfred Wegener Institute for Polar and Marine Research, Department of Ecophysiology and Ecotoxicology, Am Handelshafen 12, 27570 Bremerhaven, Germany.
Aquat Toxicol. 2004 Jul 30;69(1):1-10. doi: 10.1016/j.aquatox.2004.03.003.
Marine organisms and especially those living in tidal zones are confronted with dramatic changes in their environment such as temperature fluctuations on a daily and/or seasonal basis. In the present study, we investigated whether these parameters affect expression of multixenobiotic resistance (MXR)-related genes that serve as a first line of defense against a broad spectrum of natural and man-made toxicants. Expression of MXR-related genes seems to be an appropriate biomarker to determine hazardous effects of chemicals in contaminated marine habitats. The interference of natural environmental factors in the expression of biomarkers is an important issue with respect to the use of biomarkers in monitoring biological effects of pollutants, making interpretations difficult. We studied the effects of temperature, salinity and oxygen supply (anaerobiosis) on expression of MXR-related genes in gills and digestive gland of the blue mussel Mytilus edulis in order to differentiate between pollution-induced stress and responses to natural environmental variations. We found changes in expression levels of P-glycoprotein (pgp), major vault protein (mvp), topoisomerase II (topoII), heat shock protein 70 (hsp70), but not of the multidrug resistance-related protein (mrp2) genes, in laboratory experiments in relation to high temperature, low salinity and anaerobiosis but not low temperature. These effects of environmental factors have to be considered in sampling strategies for monitoring programmes to prevent false interpretation of results.
海洋生物，尤其是生活在潮间带的生物，面临着其环境中的剧烈变化，如每日和/或季节性的温度波动。在本研究中，我们调查了这些参数是否会影响多药耐药性（MXR）相关基因的表达，这些基因作为抵御广泛的天然和人造毒物的第一道防线。MXR相关基因的表达似乎是确定受污染海洋栖息地中化学物质有害影响的合适生物标志物。在利用生物标志物监测污染物的生物效应方面，自然环境因素对生物标志物表达的干扰是一个重要问题，这使得解释变得困难。我们研究了温度、盐度和氧气供应（无氧状态）对蓝贻贝紫贻贝鳃和消化腺中MXR相关基因表达的影响，以便区分污染引起的应激和对自然环境变化的反应。在实验室实验中，我们发现与高温、低盐度和无氧状态相关，但与低温无关，P-糖蛋白（pgp）、主要穹窿蛋白（mvp）、拓扑异构酶II（topoII）、热休克蛋白70（hsp70）的表达水平发生了变化，但多药耐药相关蛋白（mrp2）基因的表达水平未发生变化。在监测计划的采样策略中必须考虑环境因素的这些影响，以防止对结果的错误解读。
