Sustained-Release Buprenorphine Improves Postsurgical Clinical Condition but Does Not Alter Survival or Cytokine Levels in a Murine Model of Polymicrobial Sepsis

Cecal ligation and perforation (CLP) is a common technique for studying sepsis in mice. Because of the invasiveness of the procedure and its effects on clinical condition, many animal care and use committees require the use of analgesics with CLP. However, some analgesics have immunomodulatory effects and thus can hinder the overall research outcomes of a project. Here we sought to determine the effects of buprenorphine hydrochloride (Bup HCl) compared with sustained-release buprenorphine (Bup SR) on clinical condition, plasma concentrations of monocyte chemoattractant protein (MCP) 1 and IL6, and overall mortality in a murine CLP model of sepsis. Male C57/BL6 mice underwent CLP surgery and received Bup HCl or Bup SR as a component of an IACUC-approved analgesic dosing regimen. Mice were observed twice daily for clinical condition scoring by the same blinded investigator for the duration of the study. MCP1 and IL6 levels and mortality did not differ significantly between the 2 groups. Scoring of clinical condition revealed a significant decrease in behaviors associated with perceived pain at 12 and 24 h postoperatively in mice in the Bup SR group compared with the Bup HCl group. Because of the lack of significant effect on MCP1 and IL6 levels and mortality and the superior analgesic effects of Bup SR, we recommend the use of Bup SR for analgesia during the murine CLP model of sepsis.