Department of Zoology, School of Basic Sciences, Central University of Punjab, Bathinda, India.
Department of Zoology, Institute of Science, Banaras Hindu University, Varanasi, India.
Andrologia. 2022 Oct;54(9):e14507. doi: 10.1111/and.14507. Epub 2022 Jun 26.
Thyroid hormone (T ) acts on the testis via thyroid hormone receptor alpha 1 (TRα1), though the cellular localization of TRα1 in testis remains controversial. Studies on the presence of TRα1 in the epididymis are also lacking. The present study, therefore, examined the cellular localization and expression pattern of TRα1 in testis and epididymis of Parkes mice during postnatal development. Immunohistochemical results showed localization of TRα1 in interstitial and tubular compartments of the testis all through the development. On postnatal day (PND) 14, only leptotene spermatocytes showed TRα1-immunoreactivity in the testis, while at PND 28, 42, and 90, a diverse staining pattern for TRα1 was seen in almost all the seminiferous tubules mainly in leptotene spermatocytes, round and elongating spermatids, and in Leydig cells. Further, qRT-PCR and immunoblot analyses showed that TRα1 was expressed in the testis at the transcript as well as protein level throughout the postnatal development. TRα1 was also seen in principal cells of the epididymis, with maximal expression at PND 90. TRα1 was also present in cauda epididymidal spermatozoa of adult mice at PND 90. The results suggest that TRα1 is expressed in the testis and epididymis and that it may help to regulate the spermatogenic process and male fertility.
甲状腺激素（T）通过甲状腺激素受体α1（TRα1）作用于睾丸，尽管 TRα1 在睾丸中的细胞定位仍存在争议。关于 TRα1 在附睾中存在的研究也很少。因此，本研究在帕克斯小鼠出生后发育过程中检测了 TRα1 在睾丸和附睾中的细胞定位和表达模式。免疫组织化学结果显示，TRα1 在睾丸的间质和管状区均有定位。在出生后第 14 天（PND），只有精原细胞显示出 TRα1 免疫反应性，而在 PND 28、42 和 90 天，几乎所有的生精小管都显示出 TRα1 的不同染色模式，主要是在精原细胞、圆形和伸长的精子细胞以及间质细胞中。此外，qRT-PCR 和免疫印迹分析表明，TRα1 在整个出生后发育过程中在睾丸中均有转录和蛋白水平的表达。在附睾的主细胞中也观察到 TRα1，在 PND 90 时表达最强。在 PND 90 的成年小鼠的附睾尾部精子中也存在 TRα1。结果表明，TRα1 在睾丸和附睾中表达，可能有助于调节精子发生过程和男性生育能力。
