Ketata I, Smaoui-Damak W, Guermazi F, Rebai T, Hamza-Chaffai A
Ecotoxicologie Marine, UR 09-03, Université de Sfax, IPEIS, BP 805, 3018 Sfax, and Service nucléaire, Hôpital Habib Bourguiba, Tunisia.
Comp Biochem Physiol C Toxicol Pharmacol. 2007 Sep;146(3):415-30. doi: 10.1016/j.cbpc.2007.05.002. Epub 2007 May 24.
The gulf of Gabès is well known for its multiple contaminations which are closely associated with the past and present industrial and anthropogenic activity. In order to evaluate in situ the cadmium bioaccumulation in the clam Ruditapes decussatus sampled in this area, we measured cadmium concentrations in the whole soft tissues and in the digestive gland during one year. Energy reserves (proteins, glycogen, lipids) were monitored during gametogenesis in the remainder (mantle, adductor muscle, foot, siphons) of clams. Sex steroids (progesterone, testosterone, estradiol-17beta) were also measured by radio-immunoassay (RIA) in the gonads. The results showed that cadmium varied according to the reproductive cycle. High values were recorded at the resting stage in both sexes, during the gamete development and maturation in males and at the ripening and partially spawn stages in females. No significant changes in protein levels were observed in both females and males. However, high levels of glycogen and lipid reserves were recorded during the gametogenesis activity (from the development to the partially spawn stages). For steroid analyses, the results showed no important changes in testosterone levels all along the reproductive cycle. Fluctuations of sex steroids (especially progesterone and estradiol-17beta) could suggest their possible role as endogenous modulators of gametogenesis in R. decussatus. Correlation matrix and multiple regression models were also proposed to describe negative and significant relationship between cadmium and (glycogen, progesterone, testosterone and estradiol-17beta). These correlations may suggest the involvement of cadmium in the dysfunction of energy status and the endocrine disruption which could impede reproduction.
加贝斯湾因其多种污染而闻名，这些污染与过去和现在的工业及人为活动密切相关。为了原位评估该地区采集的蛤仔（Ruditapes decussatus）中镉的生物积累情况，我们在一年时间里测量了整个软组织和消化腺中的镉浓度。在蛤仔的其余部分（外套膜、闭壳肌、足部、虹吸管）配子发生过程中监测能量储备（蛋白质、糖原、脂质）。还通过放射免疫分析（RIA）测定了性腺中的性类固醇（孕酮、睾酮、雌二醇-17β）。结果表明，镉含量随生殖周期而变化。两性在静止期、雄性配子发育和成熟期间以及雌性成熟和部分产卵阶段均记录到高值。雌雄两性的蛋白质水平均未观察到显著变化。然而，在配子发生活动期间（从发育到部分产卵阶段）记录到高糖原和脂质储备水平。对于类固醇分析，结果表明在整个生殖周期中睾酮水平没有重要变化。性类固醇（尤其是孕酮和雌二醇-17β）的波动可能表明它们可能作为蛤仔配子发生的内源性调节剂发挥作用。还提出了相关矩阵和多元回归模型来描述镉与（糖原、孕酮、睾酮和雌二醇-17β）之间的负相关和显著关系。这些相关性可能表明镉参与了能量状态的功能障碍和内分泌干扰，这可能会阻碍繁殖。
