A quantitative microspectrophotometric study of the lead precipitation reaction for the histochemical demonstration of acid phosphatase.

The possibility of quantitating microspectrophotometrically the lead precipitation reaction for the histochemical demonstration of acid phosphatase was studied using the following models: sections of rat kidney and human prostate gland, and polyacrylamide films with incorporated prostate gland homogenate. The activity of the polyacrylamide models was previously evaluated by a biochemical method and the specificity of the reaction was controlled with specific inhibitors. Linear relations between cytophotometric reading and enzymatic activity, and between optical densities and different incubation periods, were demonstrated. The results obtained indicate the validity of the microspectrophotometric quantitation for this reaction with direct readings over a wide range of the visible light spectrum.