BRAIN INTERLEUKIN-1 GENE-EXPRESSION INDUCED BY PERIPHERAL LIPOPOLYSACCHARIDE ADMINISTRATION

In an attempt to demonstrate and localize intracerebral interleukin 1 (IL-1) synthesis we examined IL-1α and mRNA expression in various brain regions after peripheral administration of bacterial lipopolysaccharide (LPS) administration. Both IL-1α and IL-1β gene expression were detected 3 hours after LPS administration by polymerase chain reaction (PCR), while no mRNA was found under basal conditions or 18 hours after injection. IL-1α and IL-1β mRNAs were differently distributed within the brain, IL-1α mRNA was found in the hippocampus while IL-1β mRNA was found in the striatum and in the thalamus. These results suggest that local synthesis of IL-1 in the brain might be responsible for IL-1 central effects. The presence of IL-1 receptor mRNA was investigated using a type I T-cell IL-1 receptor probe and no IL-1 receptor mRNA could be detected in the brain even with PCR. © 1992.