[Cholecystokinin octapeptide augments expression of anti-inflammatory cytokines in mice challenged by lipopolysaccharide].

OBJECTIVE: To observe the effects of cholecystokinin octapeptide (CCK-8) on the expression of anti-inflammatory cytokines interleukin-4 (IL-4) and IL-10 in lipopolysaccharide (LPS) challenged mice. METHODS: Kunming mice were randomly assigned into four groups (each n=7): (1) Intraperitoneal injection of LPS (10 mg/kg), and the times of peak level of IL-4 and IL-6 expression in serum and lung tissue were noted at 0, 2, 4, 6 and 12 hours after challenge. (2) Control group ( intraperitoneal injection of normal saline 0.2 ml). (3) LPS+CCK-8 group ( intraperitoneal injection of CCK-8 60 microg/kg 30 minutes before giving LPS). (4) CCK-8 group (intraperitoneal injection injection CCK-8 60 microg/kg) at different time points. The expressions of IL-4 and IL-10 in the serum and lung tissues were assayed by enzyme linked immunoadsorbent assay (ELISA) and reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: Two hours after LPS challenge, IL-4 and IL-6 were increased significantly in serum and lung tissue. At 4 hours and 6 hours, serum IL-4 and IL-6 reached their peak levels, while in lung tissue they reached their peak levels at 6 hours. Pre-treatment of CCK-8 augmented IL-4 and IL-10 expressions in LPS challenged mice (both P<0.01). But single CCK-8 injection showed no significant effect on IL-4 and IL-10 in serum and lung tissue. CONCLUSION: CCK-8 is involved in the anti-inflammatory response by increasing the expressions of IL-4, IL-10 in LPS challenged mice, and in turn it alleviates the inflammatory response in lung tissue.