Thyroid hormone receptor α1–β1 expression in epididymal epithelium from euthyroid and hypothyroid rats

Abstract

The objectives of the present work were to assess whether epithelial cells from the different segments of epididymis express TR alpha 1-beta 1 isoforms, to depict its subcellular immunolocalization and to evaluate changes in their expression in rats experimentally submitted to a hypothyroid state by injection of 131I. In euthyroid and hypothyroid groups, TR protein was expressed in epididymal epithelial cells, mainly in the cytoplasmic compartment while only a few one showed a staining in the nucleus as well. A similar TR immunostaining pattern was detected in the different segments of the epididymis. In hypothyroid rats, the number of TR-immunoreactive epithelial cells as well as the intensity of the cytoplasmic staining significantly increased in all sections analyzed. In consonance to the immunocytochemical analysis, the expression of TR alpha 1-beta 1 isoforms, assessed by Western blot revealed significantly higher levels of TR in cytosol compared to the nuclear fractions. Furthermore, TR expression of both alpha 1 and beta 1 isoforms and their mRNA levels were increased by the hypothyroid state. The immuno-electron-microscopy showed specific reaction for TR in principal cells associated with eucromatin, cytosolic matrix and mitochondria. The differences in expression levels assessed in control and thyroidectomized rats ascertain a specific function of TH on this organ.

Thyroid and male reproduction

“…Both the protein as well as mRNA levels of TR isoforms increase significantly in hypothyroid rats. [8] TRβ 1 are also identified on the nuclear membrane of PZ HPV-10 cell line derived from prostatic tissue. [9]…”

Crossover of the Hypothalamic Pituitary–Adrenal/Interrenal, –Thyroid, and –Gonadal Axes in Testicular Development

“…Recent studies in S. iseri and R. norvegicus demonstrated that tr mRNA levels fluctuate with TH production within gonadal tissues (117, 129). Moreover, the analysis of the promoter of TRα and TRβ showed putative thyroid response elements (TREs) in mice ( M. musculus ) and medaka ( Oryzias latipes ) (12), reinforcing the auto-regulation of TRs by THs.…”

Gestational and neonatal‐onset hypothyroidism alters androgen receptor status in rat prostate glands at adulthood

“…Most of the existing literature as elaborated above point out testis as the major site of thyroid hormone action among mammalian male reproductive tract organs, a view amply supported by the demonstration of specific thyroid hormone receptors (TRs) in Sertoli and Leydig cells [1,5,21]. However, a number of papers that emanated from ours and a few other laboratories indicated that the mammalian male accessory sex organs are also influenced by thyroid hormones [22][23][24][25][26][27][28][29][30][31][32].…”