Silveyra G R, Canosa I S, Rodríguez E M, Medesani D A
Dept. of Biodiversity and Experimental Biology, FCEN, University of Buenos Aires, Institute of Biodiversity, Experimental and Applied Biology (IBBEA), CONICET-UBA, Ciudad Universitaria, Pab. II, C1428EGA Buenos Aires, Argentina.
Dept. of Biodiversity and Experimental Biology, FCEN, University of Buenos Aires, Institute of Biodiversity, Experimental and Applied Biology (IBBEA), CONICET-UBA, Ciudad Universitaria, Pab. II, C1428EGA Buenos Aires, Argentina.
Comp Biochem Physiol C Toxicol Pharmacol. 2017 Feb;192:1-6. doi: 10.1016/j.cbpc.2016.10.011. Epub 2016 Nov 24.
Atrazine, a herbicide that is intensively used in Argentina, was assayed to evaluate the alteration of reproduction in a wild species of crustaceans. Adult females of the estuarine crab Neohelice granulata were exposed to formulated atrazine during the 3-month pre-reproductive period. Three atrazine concentrations (0.03, 0.3 and 3mg/L) were assayed, together with a water dilution control. At the end of the exposure period, several variables concerning the energetic status of animals were measured, such as weight gain, glycemia, and energy reserves in both muscle and hepatopancreas. The gonadosomatic index (GSI) was also determined, as well as the proportion and relative area of each oocyte type in histological sections. Besides, the total content of vitellogenin proteins (Vg) in both ovary and hepatopancreas was measured. A significant (p<0.05) decrease of glycogen content was observed in muscle, while a significant (p<0.05) lower area of both previtellogenic and vitellogenic oocytes was verified in the ovary by effect of atrazine, in correspondence with a Vg content significantly (p<0.05) diminished in the ovary and augmented in the hepatopancreas. Besides, a higher proportion of previtellogenic oocytes were seen by effect of atrazine. Taken together, these results indicate a clear reduction and delay in the ovarian growth of the studied species, during the period at which the ovary normally grows up prior to spawning. On the other hand, a decrease of Vg content was observed at 0.3 and 3mg/L of atrazine after 24-h in vitro assays carried out with ovarian explants, providing additional evidence about the inhibitory role of this herbicide on the ovarian growth. These results encourage future research on deleterious effects of atrazine on crustacean reproduction.
莠去津是一种在阿根廷大量使用的除草剂，本研究对其进行了分析，以评估其对一种野生甲壳类动物繁殖的影响。河口蟹粒突新海伦蟹的成年雌蟹在3个月的繁殖前期暴露于配制好的莠去津中。研究了三种莠去津浓度（0.03、0.3和3mg/L），并设置了一个水稀释对照组。在暴露期结束时，测量了与动物能量状态相关的几个变量，如体重增加、血糖以及肌肉和肝胰腺中的能量储备。还测定了性腺指数（GSI），以及组织切片中每种卵母细胞类型的比例和相对面积。此外，还测量了卵巢和肝胰腺中卵黄蛋白原（Vg）的总含量。观察到肌肉中的糖原含量显著（p<0.05）下降，而由于莠去津的作用，卵巢中前卵黄生成期和卵黄生成期卵母细胞的面积显著（p<0.05）减小，同时卵巢中Vg含量显著（p<0.05）降低，而肝胰腺中的Vg含量增加。此外，由于莠去津的作用，前卵黄生成期卵母细胞的比例更高。综上所述，这些结果表明，在所研究的物种中，卵巢在正常产卵前生长的时期，其生长明显减少和延迟。另一方面，在用卵巢外植体进行的24小时体外试验中，在0.3和3mg/L的莠去津浓度下观察到Vg含量下降，这为这种除草剂对卵巢生长的抑制作用提供了额外的证据。这些结果鼓励未来对莠去津对甲壳类动物繁殖的有害影响进行研究。
