THE DISTRIBUTION OF ESTROGEN-RECEPTORS IN THE URINARY-TRACT OF THE MALE RABBIT - AN IMMUNOHISTOCHEMICAL AND BIOCHEMICAL-STUDY

The distribution of estrogen receptors (ER) in the urinary system in t he male rabbit were investigated in 18 mature and healthy rabbits by i mmunohistochemical examination of tissue samples taken from renal pelv is, mid-ureter, bladder-top, posterior urethra and the prostate. ER we re detected in 17 out of 18 cases in the urothelial lining and the sub epithelial stromal cells of the posterior urethra; and in 15 out of 18 cases in prostatic stromal cells. ER was not found in bladder-top, mi d-ureter or renal pelvis. Receptor determination in the isolated cytos olic and nuclear fraction, showed that the mean prostatic receptor den sity were 151.5 f mol/mg protein in the nuclear and 51.4 in the cytoso lic fraction. The corresponding mean values obtained from the posterio r urethra were 128.2 and 88.9 f mol/mg protein. We conclude, that ER c an be demonstrated in the urinary system of the male rabbit, and these are restricted to the posterior urethra and the prostatic stromal tis sue.