Intracerebral transplantation of the genital tubercle in the rat: the fate of the penile bone and cartilages.

Genital tubercles of 70 newborn male and female rats were transplated into the brains of unrelated infant rats. Seven other tubercles were placed subcutaneously. All female, and some male, hosts were injected with testosterone propionate. After surviving from 2-24 days,, histological study of 49 successful grafts showed survival of the urethral and balano-preputial epithelia and growth of the preputial glands, which formed secretion-filled cysts and became the major component of the graft. The fate of the mesodermal tissues witin the glands varied between remaining in an undeveloped state, with only pale fibrouw tissue and an area of granular degeneration and giant cells, and achieving an incompletely differentiatel state in which erectile tissue and the anterior process of fibrocartilage had formed and the glans had grown but the penile bone and its secondary growth cartilage failed to appear. Grafts could reach this degree of differentiation of the glands irrespective of transplantation site, attachment to the host dura, the sex of donor or host, and whether or not male hosts were given exogenous hormone.