Morphology, endocrinology, and environmental modulation of gonadal sex differentiation in teleost fishes
Morphology, endocrinology, and environmental modulation of gonadal sex differentiation in teleost fishes
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DOI：
10.1023/a:1023343023556
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发表时间：
2004
影响因子：
2.9
通讯作者：
C. A. Strüssmann;Masaru Nakamura
中科院分区：
文献类型：
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作者：
C. A. Strüssmann;Masaru Nakamura
成人的成功繁殖取决于性腺的正常个体发育，这是一个复杂的细胞和组织学分化过程，始于生命早期。这一过程在理论上是由遗传因素预先决定的，包括在成为男性或女性之前、期间甚至之后，双势性腺对内源性内分泌因素的敏感化。然而，幼鱼相对容易受到一系列环境（物理和化学）因素的影响，这些因素可以影响内源性内分泌轴，干扰甚至推翻假定的发育途径。这种性不稳定性可以被利用为我们生产最有价值的单性鱼类种群的优势，用于食品生产或观赏鱼贸易。另一方面，它也代表了内分泌干扰化学物质和气候因素，特别是环境温度的不良影响的潜在途径。本文详细介绍了性腺性别分化的早期组织学过程，特别提到了性腺物种，并回顾了用于鉴别卵巢和睾丸分化的标准。它还回顾了在各种鱼类基因型性别决定的相对稳定性背景下，内分泌能力和分化性腺对外源影响的敏感性的发展。一些物种的性别分化似乎受到强烈的遗传控制，可能不需要内源性性类固醇的产生。相反，在其他物种中，性腺分化依赖内源性性类固醇，这一现象显然与环境（主要是温度）不稳定的性别分化发生率较高有关。
Successful reproduction by an adult depends on the normal ontogenesis of the gonads, a complex process of cellular and histological differentiation that starts early in life. This process is theoretically predetermined by genetic factors and includes sensitisation of the bipotential gonads to endogenous endocrine factors prior to, during and even after commitment to maleness or femaleness. However, young fish are relatively vulnerable to a host of environmental (physical and chemical) factors that can affect this endogenous endocrine axis, disturbing or even overriding the putative developmental pathway. This sexually lability can be exploited to our advantage for the production of monosex fish populations of the most valuable sex for food production or aquarium fish trade. On the other hand, it represents also a potential path for undesirable influences from endocrine-disrupting chemicals and climatic factors, particularly environmental temperature. This paper provides a detailed account of the early histological process of gonadal sex differentiation, with special reference to gonochoristic species, and reviews the criteria employed to positively identify ovarian and testicular differentiation. It also reviews the development of endocrine competence and sensitivity of the differentiating gonads to exogenous influences in the context of the relative stability of genotypic sex determination in various fish species. Sex differentiation in some species seems to be under strong genetic control and may not require endogenous sex steroid production. Conversely, reliance on endogenous sex steroids for gonadal differentiation is observed in other species and this phenomenon is apparently associated with a higher incidence of environment (mainly temperature)-labile sex differentiation.