ENZYME HISTOCHEMISTRY OF BONE INDUCTION BY URINARY BLADDER EPITHELIUM

Open Access
Publisher Website
Google Scholar
Abstract
Homogenous transplants of urinary bladder mucosa were made in guinea pigs, and induced bone formation was observed histochemically for alkaline phosphatase, acid phosphatase, esterase, β-glucuronidase, aminopeptidase, and oxidative enzymes, i.e., succinic dehydrogenase, diphosphopyridine nucleotide-dependent dehydrogenase (lactate, malate, glutamate, α-glycerophosphate, β-hydroxybutyrate) and triphosphopyridine nucleotide-dependent dehydrogenase (glucose-6-phosphate and isocitrate). Normal urinary bladder epithelium contained intense alkaline phosphatase and slight acid phosphatase activity throughout. There was weak esterase activity in intermediate layer and weak β-glucuronidase activity in intermediate layer. Succinic dehydrogenase was present throughout the epithelium, and was most active in the basal layer. Lactic and malic dehydrogenase activities were intense. Glutamic, α-glycerophosphate and β-hydroxybutyric dehydrogenase activities were low, but glucose-6-phosphate and isocitric dehydrogenase activities were high. In the initial stage after transplantation, alkaline phosphatase, aminopeptidase and lactic dehydrogenase appeared in the connective tissue surrounding the transplanted mucosa in association with an inflammatory infiltration. Epithelial transplants formed cysts. Lactic, malic and triphosphopyridine nucleotide-dependent dehydrogenases in cystic epithelium were as intense as in normal bladder, though other enzymes decreased. Hyaline formation occurred around the cyst. No appreciable enzyme activity was demonstrated in this hyalinized portion, but when bone appeared marked activity of alkaline and acid phosphatases was seen around it. Histochemical patterns in the induced bone were essentially the same as in normal bone.