LPS and morphine in vitro stimulated release of IL-1β from splenic leukocytes differed between wild-type strains. Lines represent logistic fitted dose-response curve.
Panel A: LPS stimulation yielded clear dose-response curves with similar EC50 values but different efficacies between strains. C57BL/6 mice displayed the highest maximal response, whilst CBA the least, and Balb/c mice were in-between.
Panel B: Morphine stimulation did not induce IL-1β expression except at 100 μM. C57BL/6 mice displayed the highest response, whilst CBA the least, and Balb/c mice were in-between.