Effects of in vivo indomethacin treatment in aging mice

The effects of in vivo treatment with indomethacin were assessed in aging (22-36 month old) as compared to young (2-3 month old)F1 (C3H/ebJ x C57BL/6J) mice. Old mice manifested erythropenia, which was not apparent in the young. In leukocyte level there was a more rapid decrease in the old, following an initial increase in both age groups. The response of peripheral blood leukocytes (PBL) of both young and old mouse groups to mitogens decreased after treatment with indomethacin, yet in the old a significant increase (3- to 4-fold) was subsequently noted. Similarly, splenocyte response to PHA decreased initially and then increased in both age groups. This dynamics of changes was not observed in ConA-stimulated splenocytes of the old mice. Levels of IL-1 activity in culture supernatants of adherent splenocytes from indomethacin treated old mice were higher than those of the untreated age-mates. Conversely, in the young, in vivo treatment with indomethacin led to reduced IL-1 levels. The pattern of effects of indomethacin thus seems to be altered in aging.