RESUMEN
The effects of ribavirin (1-beta-D-ribofuranosyl-1,2,4-triazole-3-carboxamide, RTC) on natural killer (NK) activities of murine spleen cells in vitro were studied by 125I-UdR isotope release assay. The results showed that RTC at the concentration of 5 mumol.L-1 significantly suppressed NK activities (P < 0.01), and a negative correlation between NK activities and RTC dosage was obtained. It also indicated that there was additive effect between the actions of RTC and dexamethasone (Dex, 1 mumol.L-1), and antagonism between the actions of RTC and interferon-gamma (100 U.ml-1). In addition, RTC at the concentration of 0.5 mumol.L-1 was found to be enough to reduce the product of interferon (P < 0.01) and interleukin-2 (P < 0.05) induced by Con A in murine spleen cells, and a negative dose-effect relationship was observed. Thus, one of the mechanisms of RTC in inhibiting NK activities seems to suppress the production of these lymphokines.