Early deviations of testicular Leydig cells in the naturally unilateral cryptorchid pig.

Abstract

In this study, histomorphometric, histologic and histochemical aspects of the Leydig cell development of the abdominal and scrotal testis of the naturally unilateral cryptorchid perinatal pig were examined. In the pig, Leydig cells differentiate from about 2.5 weeks before to 2.5 weeks after birth, followed by regression up to 7 weeks. Within 2 weeks after birth, initial deviations were recognized in the intertubular Leydig cells of the abdominal testis. When compared with their homologs in the scrotal testis, they revealed reduced presence of enzyme histochemical activity of 3n-HSD and 17(3-HSD, reduced number of fuchsinophilic granules, increased number of sudanophilic droplets and cellular vacuoles and changes in cellular location of 1 7j3-HSD. At about 4 weeks after birth, cell volume of both peritubular and intertubular Leydig cells was slightly reduced, but marked histomorphometrical deviations did not develop until 10 weeks after birth. Most data from the scrotal testis of the unilaterally cryptorchid pig were within the range for normal pigs. When the abdominal testis is compared with the scrotal testis, it is concluded that in the former, the postnatal part of the Leydig cell development is accomplished to a lesser degree and that the subsequent regression of the Leydig cell is accelerated. It is suggested that after birth, the temperature difference between scrotal and abdominal testes is a major factor in the development of differences between their respective Leydig cells.