Antagonistic effect of heparin and a water-soluble glucocorticoid on the peripheral lymphocyte count in mice

The effect of heparin and prednisolone succinate on the peripheral white blood cell count of mice has been studied 3 hours after injecting the drugs. Heparin in low doses did not influence the cell count but in higher doses (20 to 400 U) elicited marked lymphocytosis. When prednisolone and heparin were administered together, heparin (5 to 10 U) markedly inhibited the prednisolone-induced lymphopenia. The effect on the lymphocyte count of prednisolone combined with a large dose of heparin depends on the doses of the drugs. The antagonism seems to be non-competitive in nature. The PMN count shows only minor changes and the reaction of eosinophils to heparin is less pronounced. The antagonistic effect was manifest on the spleen weight.