Toxicity and Dose Response of Intra-Abdominally Administered Poly-L-alpha-Lysine and Poly-L-Glutamate for Postoperative Adhesion Protection

Background/Aims: Two differently charged polypeptides, poly-L-lysine (PL) and poly-L-glutamate (PG), have previously been shown to reduce postoperative intra-abdominal adhesions. This study aims to investigate the possible toxic effects and to establish a lowest effective antiadhesive dose. Methods: 152 mice were investigated with a well-known adhesion model and given different concentrations of the two differently charged polypeptides as well as only the cationic PL. Results: For the first time, a probable toxic level of PL given intraperitoneally (40 mg/kg) and the lowest significant concentration of PL and PG for antiadhesive purposes (1.6 mg/kg) could be established. Conclusion: The gap between the possible toxicity level of PL and the lowest efficient antiadhesive dose is probably too narrow, and the shape and charge of PL warrant continuous research for another poly-cation in the concept of differently charged polypeptides used as antiadhesive agents. Copyright (C) 2009 S. Karger AG, Basel