Differential induction of interleukin-I beta mRNA in the brain parenchyma of Lewis and Fischer rats after peripheral injection of lipopolysaccharides.

The expression of interleukin-1 beta (IL-1beta) mRNA was compared in the brain of inflammatory susceptible LEW/N and resistant F344/N rats at 3, 6, and 12 h after peripheral administration of lipopolysaccharide (LPS) or saline. No differences between strains were observed in the circumventricular organs (CVOs) and choroid plexus. At 12 h after LPS administration, increased IL-1beta mRNA expression was detected in the hypothalamus of LEW/N rats. In contrast, increased IL-1beta mRNA expression was detected in the cerebral cortex of F344/N rats. These data show region-specific differences of IL-1beta mRNA expression in the brain of these rat strains that differ in their susceptibility to inflammation.