The effect of X-irradiation on the sodium-potassium-activated adenosine triphosphatase (Na-K-ATPase) activity in the epithelium of the rat lens. A histochemical and biochemical study.
The epithelial Na-K-ATPase activity of the rat lens was studied after X-irradiation at intervals of three to ninety days. The enzyme was demonstrated histochemically by light microscopy and it was measured biochemically by a fluorometric method. Neither histochemical nor biochemical changes of Na-K-ATPase content of the lens epithelium were observed during the development of cataract. In whole-mount preparations the enzyme activity was localized in the cell membranes. However, one month after radiation a few peripheral cells had in addition a precipitated over the whole cell. The unaltered Na-K-ATPase content in the epithelium suggests that the hydration of the lens after X-irradiation is primarily caused by changes in the passive permeability properties of the cell membranes and not by a decreased capacity of the activity cation pump.
D000251:Adenosine Triphosphatases / Q000378:metabolism*; D000818:Animals; D002386:Cataract / Q000209:etiology; D002462:Cell Membrane / Q000201:enzymology; D003593:Cytoplasm / Q000201:enzymology; D004789:Enzyme Activation; D004848:Epithelium / Q000201:enzymology / Q000528:radiation effects; D005260:Female; D006651:Histocytochemistry; D007908:Lens, Crystalline / Q000201:enzymology* / Q000528:radiation effects; D011188:Potassium / Q000378:metabolism; D051381:Rats; D012964:Sodium / Q000378:metabolism; D013997:Time Factors
D012964:Sodium; D000251:Adenosine Triphosphatases; D011188:Potassium