PROSTATE AND MENADIOL SODIUM DIPHOSPHATE

MENADIOL SODIUM DIPHOSPHATE AS A NEW SUBSTARATE FOR MEASURING ACID PHOSPHATASE ACTIVITY AND A DISCUSSION ON PROSTATIC TUMOR MODEL

Abstract

Menadiol sodium diphosphate (MSDP), which is employed clinically as a water-soluble vitamin K active drug, is used as a substrate for acid phosphatase determination. A method was developed with this new substrate, and its specificity in prostatic acid phosphatase determination was estimated through comparing the rate of hydrolysis of MSDP by human prostatic tissue with those of the kidney and liver tissues (P/K, P/L ratios). These ratios were also compared in animal experiments (dog and rat), between MSDP and other substrates (p-nitrophenyl phosphate and sodium thymolphthalein monophosphate) as well. The results suggest that this new substrate is comparatively specific for the prostatic acid phosphatase than the other commonly used substrates.
On the other hand, the prostatic tumor model experiments was devised for introduction into in vivo study of this agent. Experimental prostatic tumors were made in Wistar strain male rats by local administration of 20-methylcholanthrene (20-MC), and heterotransplantation of human prostatic tumors into nude mice. The acid phosphatase activities in tissues of these tumors were evaluated with MSDP as substrate and these values were compared with those of their proper organs (kidney and liver). In two rats (20%), 20-MC induced prostatic tumor was observed. Their histologic features were of fibrosarcoma. The acid phosphatase activity in these tumor was of slightly higher level than that of the prostatic tissues of normal rat. However, these values were fairly lower than those of their own liver and kidney. In nude mice, heterotransplantation of primary tissue fragments from human prostatic adenoma provided the best results. All tissues were taken (100%) and their histologic features were strikingly similar to the original tumors. The acid phosphatase activity in those tumor tissues was significantly higher than those of their own organs; prostate (approximately 43 times), liver (approx. 26 times), and kidney (approx. 23 times). Histochemical study by means of the azo-dye coupling technique demonstrated a great activity of acid phosphatase in the glandular epithelium of prostatic adenoma which was heterotransplanted into nude mice.