The onset of spermatogenesis in fish.
The onset of spermatogenesis in fish.
复制标题
鱼类精子发生的开始。
DOI：
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发表时间：
1994
期刊：
影响因子：
--
通讯作者：
T. Kobayashi
中科院分区：
文献类型：
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作者：
Y. Nagahama;T. Miura;T. Kobayashi
在培养条件下，雄性日本鳗鲡（Anguilla japonica）的未成熟睾丸仅含精原细胞，睾丸体细胞、间质细胞和支持细胞失活。利用最近开发的鳗鱼睾丸器官培养系统，我们已经表明，鳗鱼睾丸中激素诱导精子发生涉及促性腺激素刺激间质细胞产生11-酮睾酮，这是鱼类的一种强效雄激素。反过来，11-酮睾酮激活支持细胞刺激有丝分裂前精原细胞完成精子发生。我们目前的研究重点是分离和表征在促性腺激素诱导的精子发生过程中显示在鳗鱼睾丸中表达改变的基因。已分离出1个上调基因和3个下调基因。Northern blot分析和原位杂交显示，促性腺激素注射前睾丸中缺乏激活素B mRNA，而注射促性腺激素后1 ~ 6天睾丸Sertoli细胞中激活素B mRNA含量丰富。激活素B mRNA的刺激伴随着精原细胞的增殖。促性腺激素治疗还会导致睾丸3 β -羟基类固醇脱氢酶mRNA浓度的迅速升高，该酶是促性腺激素诱导的11-酮睾酮生成的限速酶。我们还获得了三个下调的cdna，它们在促性腺激素治疗前在睾丸中含量丰富，注射促性腺激素后一天在睾丸中几乎完全消失。
Under cultivation conditions, male Japanese eels (Anguilla japonica) have immature testes containing only spermatogonia together with inactive testicular somatic cells, Leydig cells and Sertoli cells. Using a recently developed organ culture system for eel testes, we have shown that hormonal induction of spermatogenesis in eel testes involves gonadotropin stimulation of Leydig cells to produce 11-ketotestosterone, a potent androgen in fish. In turn, 11-ketotestosterone activates Sertoli cells to stimulate premitotic spermatogonia to complete spermatogenesis. Our current research focuses on the isolation and characterization of genes that show altered expression in eel testes during gonadotropin-induced spermatogenesis. One up-regulated and three down-regulated genes have been isolated. Northern blot analysis and in situ hybridization reveal that mRNA for activin B is absent in testes before gonadotropin injection and is abundant in Sertoli cells in testes injected with gonadotropin for one to six days after injection. This stimulation of activin B mRNA is accompanied by spermatogonial proliferation. Gonadotropin treatment also causes a rapid rise in the testicular concentrations of mRNA for 3 beta-hydroxysteroid dehydrogenase, the rate-limiting enzyme for gonadotropin-induced 11-ketotestosterone production. We have also obtained three down-regulated cDNAs which are abundant in testes before gonadotropin treatment and disappear almost completely in testes one day after gonadotropin injection.
在无血清培养基中培养的非洲爪蟾睾丸外植体中精子发生的体外维持。
影响因子：
3.6
作者：
Risley,MS;Miller,A;Bumcrot,DA
通讯作者：
Bumcrot,DA