Abstract
Phosphamidase activity was studied in organs and tissues of the rat, using the modification of Gomori's histochemical technique suggested by Meyer and Weinmann. Enzyme activity was allowed to go on for periods varying between 1 and 3.5 hrs. Earliest appearance, rate of increase, reproducibility and cellular distribution of staining were observed. Sites of high activity (visible precipitation in 1 to 1.5 hrs. of enzyme action) were found in epithelia and nerve tissue. High phosphamidase activity in epithelia occurred in the cells specialized for active transfer and other types of physico-chemical work, in exocrine and endocrine glands synthesizing nonprotein compounds and in tissues undergoing histodifferentiation in the adult animal. The sites of high enzyme activity in nerve tissue were found to be neuropil and nerve processes of the central nervous system and the cytoplasm of autonomic ganglion cells and nerve processes of the peripheral nervous system.
Phosphamidase activity was found absent in 3.5 hr. periods of enzyme action from epitheial cells specialized for passive transfer, from unspecialized cells and from many glands synthesizing proteins, further from the cell bodies of the cells in the central nervous system and from muscle of all types. Comparison of distributions shows phosphamidase activity demonstrably distinct from acid and alkaline phosphomonoesterase for a number of organs. Comparison of the distributions shows the sites of high phosphamidase activity to be in those tissues which do not respond to insulin stimulation; conversely, the tissues in which transfer of simple sugars is mediated by insulin do not show phosphamidase activity. A role in energy metabolism complementing the action of insulin is tentatively suggested for phosphamidase.