Department of Clinical Sciences of Companion Animals, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands.
Theriogenology. 2012 Oct 15;78(7):1618-26. doi: 10.1016/j.theriogenology.2012.07.010.
Normal sexual differentiation depends on completion of chromosomal sex determination, gonadal differentiation, and development of the phenotypic sex. An irregularity in any of these three steps can lead to a disorder in sexual development (DSD). We examined nine dogs with DSD by abdominal ultrasonography, laparotomy, histologic examination of the gonads, and reproductive tract, cytogenetic analysis, and mRNA expression of the SRY gene. We also determined the plasma concentrations of luteinizing hormone (LH), estradiol-17β, and testosterone before and after administration of gonadotropin-releasing hormone (GnRH) and compared these results with those obtained in anestrous bitches and male control dogs. The gonads of three dogs with DSD contained both testicular and ovarian tissue, while in the other six only testicular tissue was found. Each of the dogs had a uterus. Based on gynecologic examination, cytogenetic analysis, and the histology of the gonads, seven of the nine dogs appeared to be XX sex reversals. Three of these were XX true hermaphrodites and four were XX males; the other two dogs had incomplete XY gonadal dysgenesis. All seven XX sex-reversed dogs were found to be negative for the SRY gene by polymerase chain reaction. The basal plasma luteinizing hormone (LH) concentration was significantly higher in dogs with DSD than in anestrous bitches but not significantly different from that in male dogs. The basal plasma LH concentration increased significantly after GnRH administration in all dogs with DSD. The basal plasma estradiol concentration was significantly higher in dogs with DSD than in anestrous bitches but not significantly different from that in male dogs. The basal plasma testosterone concentration was lower in dogs with DSD than in male dogs. In all dogs with DSD both the basal and GnRH-induced plasma testosterone concentrations were above the upper limit of their respective ranges in the anestrous bitches. In conclusion, the secretion of LH and estradiol in these dogs with DSD, all of which had testicular tissue in their gonads, was similar to that in male control dogs. These results indicate that the basal and/or GnRH-stimulated plasma testosterone concentration might be used to detect the presence of testicular tissue in dogs with DSD.
正常的性别分化依赖于性染色体决定、性腺分化和表型性别的发育的完成。这三个步骤中的任何一个不规则都可能导致性发育障碍（DSD）。我们通过腹部超声、剖腹术、性腺和生殖道组织学检查、细胞遗传学分析以及 SRY 基因的 mRNA 表达，检查了 9 只患有 DSD 的狗。我们还测定了促性腺激素释放激素（GnRH）给药前后黄体生成素（LH）、雌二醇-17β和睾酮的血浆浓度，并将这些结果与乏情母犬和雄性对照犬的结果进行了比较。3 只 DSD 犬的性腺中同时含有睾丸和卵巢组织，而其余 6 只仅发现睾丸组织。所有犬都有子宫。根据妇科检查、细胞遗传学分析和性腺组织学，9 只犬中的 7 只似乎为 XX 性反转。其中 3 只为 XX 真两性畸形，4 只为 XX 男性；另外 2 只犬为不完全性 XY 性腺发育不良。所有 7 只 XX 性反转犬的 SRY 基因聚合酶链反应均为阴性。DSD 犬的基础 LH 浓度明显高于乏情母犬，但与雄性犬无显著差异。所有 DSD 犬的基础 LH 浓度在 GnRH 给药后均显著升高。DSD 犬的基础雌二醇浓度明显高于乏情母犬，但与雄性犬无显著差异。DSD 犬的基础睾酮浓度低于雄性犬。所有 DSD 犬的基础和 GnRH 诱导的血浆睾酮浓度均高于乏情母犬各自范围内的上限。总之，这些 DSD 犬（其性腺中均有睾丸组织）的 LH 和雌二醇分泌与雄性对照犬相似。这些结果表明，基础和/或 GnRH 刺激的血浆睾酮浓度可能用于检测 DSD 犬中睾丸组织的存在。
