Figure 1.

(A and B) Renal mRNA responses to LPS injection in control and LPS-PC mice. Mice that were pretreated with LPS 18 h previously had modest but significant TNF-α and MCP-1 mRNA elevations, compared with control (C) mice. When the LPS-PC mice were rechallenged with LPS, significantly greater increases in TNF-α and MCP-1 mRNA were observed, versus those seen in LPS-challenged naive controls. This was true whether the measurements were made at 15 (A) or 30 min (B) after repeat LPS injection. HO-1 mRNA levels were approximately twice as high in the preconditioned versus the control mice (P < 0.01); however, no acute increases were seen in either group at either 15 or 30 min after LPS injection. LPS, 15 or 30 min after LPS injection; PC, 18 h after LPS injection; PC+LPS, preconditioned mice rechallenged with LPS.