A study of the capacity for regeneration of rat and human Leydig cells.

The capacity of Leydig cells for regeneration was investigated in 12 patients with prostatic carcinoma, who underwent subcapsular orchidectomy, and in rats after testicular necrosis produced by cadmium chloride. In rats, reappearance of Leydig cells originating from the tunica albuginea could be demonstrated by histology. Testosterone concentrations increased parallel to regeneration of Leydig cells, while LH concentrations declined. In contrast to these findings, no rise of testosterone concentrations could be observed in patients up to 8 months after subcapsular orchidectomy. Human Leydig cells seem to have no capacity for regeneration, or endocrine function, despite the fact that some of these cells, which are present morphologically in the tunica albuginea or spermatic cord, remained.