Ji. Tanabe et al., DEXAMETHASONE INHIBITS THE PRODUCTION OF MACROPHAGE INFLAMMATORY PROTEIN-2 IN THE LEUKOCYTES IN RAT ALLERGIC INFLAMMATION, European journal of pharmacology, 284(3), 1995, pp. 257-263
In the air pouch-type allergic inflammation model in rats, when the in
filtrated leukocytes in the pouch fluid collected 4 h after antigen ch
allenge were incubated, neutrophil chemotactic activity in the conditi
oned medium increased time-dependently. They produced neutrophil chemo
tactic factors, viz. leukocyte-derived neutrophil chemotactic factor (
LDNCF)-2, a major component, and LDNCF-1, a minor component. When the
infiltrated leukocytes were incubated in the presence of dexamethasone
, neutrophil chemotactic activity in the conditioned medium decreased
in a concentration-dependent manner, and production of LDNCF-2 and LDN
CF-1 was inhibited. Because purified LDNCF-2 had been found to be iden
tical with rat macrophage inflammatory protein 2 (MIP-2), effects of d
examethasone on the level of MIP-2 mRNA in the leukocytes were investi
gated. Using the reverse transcription-polymerase chain reaction techn
ique, it was demonstrated that dexamethasone suppressed the level of M
IP-2 mRNA in the leukocytes. These results indicate that dexamethasone
inhibits MIP-2 production at the transcription level.