Histological process and dynamics of germ cell degeneration in pejerrey Odontesthes bonariensis larvae and juveniles during exposure to warm water.
Histological process and dynamics of germ cell degeneration in pejerrey Odontesthes bonariensis larvae and juveniles during exposure to warm water.
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DOI：
10.1002/jez.a.10249
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发表时间：
2003-06
期刊：
影响因子：
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通讯作者：
L. S. Itó;M. Yamashita;C. A. Strüssmann
中科院分区：
文献类型：
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作者：
L. S. Itó;M. Yamashita;C. A. Strüssmann
温度升高会导致阴囊哺乳动物雄性生殖细胞的退化和消失。最近的研究表明，热诱导的生殖细胞退化也发生在鱼类中，但与哺乳动物不同的是，它不仅发生在雄性动物中，也发生在雌性动物中。摘要本研究旨在探讨热诱导波那里齿鲷仔稚鱼生殖细胞消失的组织学过程与动态。通过热处理性别（温度依赖性性别决定）产生的单性别和混合性别的鱼进行29摄氏度的1至12周之间的时间，并用于分析，通过组织学方法，在性腺大小和正常和退化的生殖细胞的数量的变化。暴露于29摄氏度8-12周的组随后被转移到24摄氏度，以验证任何性腺损伤是否是永久性的。生殖细胞变性，组织学特征为核固缩或嗜酸性粒细胞增多和细胞质嗜酸性粒细胞增多，在较高温度（29>24> 17 ℃）下观察到的频率增加，男性多于女性。生殖上皮的明显退行性变化通常在暴露于29摄氏度的一周内开始，女性比男性更明显。只有在暴露于29摄氏度8-12周的个体中观察到生殖细胞的完全丧失，但没有处理产生100%无菌鱼。暴露于29摄氏度后仍留在性腺中的生殖细胞保留了快速使生殖细胞耗尽区域增殖的能力，这表明性腺中相关的体细胞很少或不受此温度的影响。
Elevated temperature causes degeneration and disappearance of the germ cells in the males of scrotal mammals. It was recently shown that heat-induced germ cell degeneration occurs also in fish but, unlike in mammals, it occurs not only in males but also in females. The purpose of this study was to clarify the histological process and dynamics of heat-induced germ cell disappearance in pejerrey Odontesthes bonariensis larvae and juveniles. Monosex and mixed-sex fish produced by thermal manipulation of sex (temperature-dependent sex determination) were subjected to 29 degrees C for periods between 1 and 12 weeks, and used to analyze, by histological methods, the changes in gonadal size and the number of normal and degenerating germ cells. Groups exposed to 29 degrees C for 8-12 weeks were subsequently transferred to 24 degrees C to verify if any gonadal damage would be permanent. Germ cell degeneration, histologically characterized by nuclear pyknosis or eosinophilia and cytoplasmic eosinophilia, was observed with increasing frequency at higher temperatures (29>24> 17 degrees C) and more in males than in females. Clear degenerative changes in the germinal epithelium usually began within one week of exposure to 29 degrees C and appeared clearer in females than in males. Complete loss of germ cells was observed only in individuals exposed for periods of 8-12 weeks to 29 degrees C but no treatment produced 100% sterile fish. Germ cells that remained in the gonads after exposure to 29 degrees C retained the capacity to rapidly recolonize germ cell-depleted areas, suggesting that the associated somatic cells in the gonads are little or not affected by this temperature.