Reversible Inactivation of Acid Phosphatase in Human Prostatic Fluid

Abstract

FOLLOWING our demonstration that the ‘acid phosphatase’, in human prostate homogenates, is incompletely and reversibly inactivated by incubation in the presence of calcium ions^1–3, we have confirmed the same reversible inactivation in the fluid obtained by massage of the prostate of individuals with normal prostates. The methods used have been described in our previous publications. Table 1 gives the results obtained in nine experiments on nine different prostatic fluids. The results are expressed as a percentage of a calculated initial value of 100. As compared with the original values, incubation in the absence of calcium ions resulted in little inactivation (mean 11.4) while, in the presence of calcium ions, inactivation amounted to a mean value of 52.6 per cent. When the concentration of calcium ions was increased to 12–18 mgm. per cent, inactivation was increased to a mean value of 81.9 per cent.