Avery A. Sandberg

A micromethod for the measurement of estrogen receptors using high pressure liquid chromatography

Adequate sample size has been one of the difficulties encountered in routine determination of estrogen receptors in prostatic disease. The recent commercial availability of protein analysis columns for use with high pressure liquid chromatography (HPLC) equipment has made the achievement of a considerable reduction in sample size feasible. We present a method for determination of ER which includes the use of 16 alpha-125-iodo-estradiol ( [125I]-E2) of 1600 Ci/mmol specific activity, the use of G-25 column chromatography, followed by fractionation by HPLC and finally relation of the fmol specifically bound to mg protein measured in the HPLC peak. Data obtained upon determination of ER in the immature rat uterine model system are given to show consistent recoveries, ligand specificity, saturability, inhibition, and commonly accepted KD and n values for this system. Also, in a pilot study on 13 samples from human prostatectomies, the utility of the HPLC technique for ER measurement in that tissue using single point analysis is demonstrated. For comparison, all receptor determinations reported were also made using conventional methods.

5α-Reductase as a Target Enzyme for Anti-Prostatic Drugs in Organ Culture

Short-term organ culture of rat and human prostatic tissues has been utilized as a means of testing drugs potentially useful in cancer of the prostate. Optimal conditions, particularly the concentrati

Changes of an androgen-dependent nuclear protein during functional differentiation and by dedifferentiation of the dorsolateral prostate of rats.

Nuclei of the dorsolateral prostate of rats contain a large amount of androgen-dependent non-histone protein (20K-NHP) (mol. wt. not equal to 20,000; pI not equal to 11.5) (Matuo et al. (1]. Its content in the nuclei increased most markedly during 4-8 weeks of age, when functional differentiation of the prostate was most active on the basis of the changes of major cytosol proteins and zinc. Nuclei of the Dunning tumors originating in the dorsolateral prostate were found to lack 20K-NHP regardless of androgen dependency, indicating the disappearance of the 20K-NHP from the nuclei by dedifferentiation. These suggest that the 20K-NHP is an important nuclear protein for differentiation of the dorsolateral prostate cells.

Effects of testosterone on estracyt localization in rat prostate.

Testosterone administration to castrated rats leads to increased concentrations of radioactivity associated with estracyt (a conjugate of carbamate with E2) in the prostate gland, particularly the ventral prostate. This contracts with the decreased concentrations of labeled E2. The findings appear to shed further light on the possible mechanism of action of estracyt in cancer of the prostate.