X-RAY-MICROANALYSIS OF BULK HYDRATED SPECIMENS OF NEOPLASTIC AND NONNEOPLASTIC HUMAN UROTHELIUM

Specimens of neoplastic and non-neoplastic human urothelium were rapid ly frozen against a copper block immersed in liquid nitrogen, planed i n a cryoultramicrotome and then examined by low-temperature scanning e lectron microscopy (LTSEM) following coating by aluminium. Energy disp ersive X-ray microanalysis (XRMA) was performed on the superficial uro thelial cells and on gelatin blocks mounted in parallel which had know n concentrations of sodium, potassium, chloride, and phosphorus. The n eoplastic urothelial cells had significantly less phosphorus (P < 0.05 ) than non-neoplastic cells and the ratios K+/P, K+/Na+, and K+/Cl- we re significantly higher in neoplastic cells than in non-neoplastic cel ls (P < 0.00001). These results are consistent with those expected in cells with a sustained increase in intracellular pH caused by stimulat ion of Na+/H+ ion membrane exchange.