Zinc and cadmium concentrations in whole tissue and in separated epithelium and stroma from human benign prostatic hypertrophic glands.

Abstract

Prostate tissues from patients with benign prostatic hypertrophy were separated into epithelial and stromal components and the concentrations of zinc and cadmium were determined in these two fractions and in whole tissue by atomic absorption spectrophotometry. The concentrations of testosterone and 5 alpha-dihydrotestosterone (5 alpha-DHT) were determined by radioimmunoassays. The concentration of zinc was found to be significantly greater (P less than .001) in epithelial than in stromal preparations: 17.32 +/- 1.15 vs. 7.29 +/- 0.53 mumol/g dry weight (SEM, n = 15). The concentrations of cadmium in epithelium, 9.55 +/- 1.31 nmol/g dry weight (SEM, n = 15) and in stroma, 6.65 +/- 1.06 nmol/g dry weight (SEM, n = 15), did not differ significantly. The concentrations of zinc and cadmium in whole tissues were 13.88 +/- 1.70 mumol/g dry weight and 8.85 +/- 1.53 nmol/g dry weight, respectively (SEM, n = 15). In epithelial preparations, cadmium and testosterone were inversely correlated, but no other correlations were noted between metal and androgen concentrations in whole tissue, stroma, or epithelium. The results of the present study indicate that zinc preferably resides in the epithelium of human prostatic tissue, particularly in BPH, although the stroma also contains significant amounts of this metal. Cadmium appears to be more evenly distributed between the epithelium and stroma of prostatic tissue and previous findings of high cadmium concentrations in hypertrophic and carcinomatous prostatic tissue were not confirmed.