Histochemistry of non-specific phosphatases: the use of p-nitrophenyl phosphate and -glycerophosphate as substrates

Synopsis It has been found that the acid and alkaline phosphatases in homogenates of respectively intestine and hypodermis ofAscaris suum hydrolyse sodiump-nitrophenyl phosphate at about twice the rate of sodium -glycerophosphate. This difference was also observed histochemically. Thus, when sections of intestine were incubated for acid phosphatase withp-nitrophenyl phosphate as substrate, the intensity of staining was about twice as great as that obtained after incubation in -glycerophosphate. Further, alkaline phosphatase was evident in sections of hypodermis after only 2 hr incubation inp-nitrophenyl phosphate but was not apparent after 10 hr incubation with -glycerophosphate. Hence biochemical assays and histochemical studies both indicate thatp-nitrophenyl phosphate is a superior substrate to -glycerophosphate for the visualization of acid and alkaline phosphatases in tissues.This paper was presented in part at the 1969 Aberdeen meeting of the British Society for Parasitology.