In vivo 31P magnetic resonance spectroscopy for evaluation of testicular function in cryptorchid rats.

PURPOSE: To assess in vivo metabolism of rat testicles in experimental cryptorchidism, we used 31P magnetic resonance (MR) spectroscopy and compared testicular MR spectroscopic parameters with flow cytometric DNA analysis.

MATERIALS AND

METHODS

In vivo 31P MR spectroscopy and flow cytometric DNA analysis of rat testis were performed before and during 14 days of experimental cryptorchidism.

RESULTS

The testicular phosphomonoester (PM)/ATP ratio showed a transient increase when multinuclear giant cells appeared in the seminiferous tubules. However, the ratio returned to the preoperative level when these cells disappeared. The phosphodiester (PD)/ATP ratio gradually decreased and the inorganic phosphate (Pi)/ATP ratio slowly increased. DNA flow cytometry showed a decrease in the percentage of haploid cells and an increase in the percentage of diploid cells from 7 days after cryptorchidism. The percentage of tetraploid cells did not change before and during cryptorchidism.

CONCLUSION

This study indicates that in vivo 31P MR spectroscopy in combination with flow cytometric DNA analysis provides useful biochemical and histological information for evaluation of testicular function.