EFFECTS OF ASPIRIN ON THE NUMBER OF PERIPHERAL WHITE BLOOD CELLS AND SPLEEN EOSINOPHILS IN GUINEA-PIGS

Effects of lysine-acetylsalicylate, a soluble form of aspirin, on the number of peripheral white blood cells (PWBC) and on the number of eosinophil granulocytes in spleen imprints were investigated in outbred male guinea-pigs. The absolute number of PWBC and different leukocyte types were determined by standard technique in a haemocytometer. The number of eosinophils in spleen imprints was determined on 2000 nucleated cells. In a dose of 50 mg/kg or 100 mg/kg b.m., i.p., daily for five days lysine-acetylsalicylate did not change the number of PWBC, lymphocytes, neutrophils and monocytes, in comparison with the controls (p>0.05). However, in a dose of 50 mg/kg, b.m., i.p. daily for 5 days, lysine-acetylsalicylate produced a statistically significant increase in the number of blood eosinophils (p<0.05), and in a dose of 50 mg/kg, i.p., daily for ten days, lysine-acetylsalycylate produced a statistically significant increase in the number of eosinophils in spleen imprints (p<0.01), in comparison with the controls. The results suggest that small doses of aspirin could selectively increase blood eosinophil production or recruitment and that prostaglandins, could inhibit eosinophil production or migration in vivo.