EFFECTS OF AMILORIDE ON TUMOR-GROWTH AND INTRACELLULAR ELEMENT CONTENT OF TUMOR-CELLS INVIVO

  • 1 January 1983
    • journal article
    • research article
    • Vol. 43  (1) , 73-77
Abstract
The effects of amiloride, a reported inhibitor of serum-stimulated Na influx, were tested on tumor growth, tumor cell proliferation and intracellular element content of cancer cells in vivo. It was previously shown that cancer cells have high intranuclear levels of Na compared to those of their normal counterpart cells; such a high level of Na may be involved in the cancer state. Amiloride, when given in a series of injections, inhibited [mouse] H6 hepatoma and [mouse] DMA/J mammary adenocarcinoma growth in vivo in a dose-dependent fashion; 3 injections of amiloride at a dose of 1.0 .mu.g/g body wt into mice bearing H6 hepatomas resulted in a significant decrease in the intranuclear content of Na but not the content of Mg, P, S, Cl or K as measured by electron probe X-ray microanalysis in the H6 hepatoma cells. Amiloride at dosages as low as 1.0 .mu.g/g body wt per injection also inhibited tumor cell proliferation as measured by the Na thymidine autoradiography labeling index. Amiloride caused no changes in the mean profile diameters of metaphase or interphase H6 hepatoma or DMA/J mammary adenocarcinoma cells, suggesting that the action of amiloride on tumor growth was not due to cell volume changes. Amiloride inhibited tumor growth and decreased the proliferation of the tumor cells in the H6 hepatomas which was correlated with a decreased intranuclear Na content.