Preserved tissue structure of efferent ductules in aromatase-deficient mice

Abstract

Estrogen receptor γ (Esr1) is proposed to play a critical role in the regulation of testicular fluid reabsorption at efferent ductules, and disruption of the Esr1 gene (Esr1-l-) resulted in marked dilation of the lurnens of efferent ductules. This study was aimed to clarify whether disruption of the gene for aromatase (Ar), an enzyme responsible for estrogen biosynthesis, results in morphological and transcriptional alterations at efferent ductules as observed in Esr1-l- mice. Histology demonstrated structural preservation of the ducts in aromatase-deficient (Ar-l-) mice. Electron microscopic examinations reveal that endocytic apparatus and tubule-cisternal endoplasmic reticulum are present in non-ciliated cells irrespective of the genotypes. However, electron-dense and acid phosphatase-negative granules and apical tubules, which are components thought to be related to membrane recycling of endosomes, are observed only in wild-type (WT) and Ar-l- mice. By contrast, the Golgi complex is highly developed in Esr1-- mice when compared with WT and Ar-l- mice. RT-PCR analysis reveals no significant differences in the expression levels of a subset of genes involved in ion transportation. Thus, from the structural and transcriptional points of view, the efferent ductules of Ar-l- mice are indistinguishable from those of WT mice. Moreover, data from electron microscopic examinations indicate the possible involvement of Esr1 in the regulation of vesicle recycling processes. © 2008 Society for Endocrinology.