The dog prostate under defined hormonal influences: an approach to experimental induced prostatic growth.

The prostate of castrated dogs following treatment with testosterone, dihydrotestosterone and androstanediol combined with 17-beta-estradiol application was analyzed by light microscopic stereology. In all three groups there is a statistically significant increase of prostatic volume and weight. There is a statistically significant increase of the relative and absolute volume of the glandular as well as of the stromal part. Seen by the absolute data there is only a statistically significant increase of the volumetric amount of the smooth muscle cells in the dihydrotestosterone and 17-beta-estradiol treated animals. Regarding tissue distribution there is no difference between the controls and the castrated testosterone and 17-beta-estradiol treated animals. Regarding the stromal part, there is no statistically significant difference between the testosterone and 17-beta-estradiol treated group and the control animals. TIn the androstanediol and 17-beta-estradiol group there is a double and in the dihydrotestosterone and 17-beta-estradiol group a four-fold increase of the stromal part. The synergistic effect of estrogens and androgens on the growth of both parts of the dog prostate--the glandular and stromal compartment--is discussed.