A Modified Rat Model of Cecal Ligation and Puncture for Adjusting the Severity of Septic Acute Kidney Injury

Abstract

Abstract Background: We aimed to establish a modified cecal ligation and puncture (CLP) rat model with omentectomy for simulating moderate-to-severe septic kidney injury (AKI). Subjects and Methods: Rats were randomly divided into four groups subjected to: Traditional CLP (n = 40); the modified CLP procedure (n = 40); sham surgery (abdominal incision only) (n = 6); and abdominal incision and omentectomy only (n = 6). We evaluated the severity of renal injury according to serum creatinine levels at 0, 24, and 48 h postoperatively and cystatin C and neutrophil gelatinase-associated lipocalin (NGAL) levels at 12 h postoperatively, graded the severity of sepsis, monitored the degree of peritonitis, and examined animal survival. Results: Compared with the traditional CLP group, the modified CLP group developed more severe sepsis at postoperative 48 h, had more severe renal pathology, and developed more severe AKI with high homogeneity. Most rats in the traditional CLP group exhibited complete wrapping of the puncture site by omentum with limited peritonitis, while partial wrapping with pus spreading was observed in some. All rats in the modified CLP group developed puncture site necrosis, with pus spreading without formation of an encapsulated abscess, and a consistent degree of peritonitis. The 7-day survival rates in the traditional and modified CLP groups were 65.0% and 50.0%, respectively. Conclusion: The traditional CLP approach was associated with an even distribution of different AKI severities among treated animals, whereas the modified CLP approach established a consistently more severe rat model of septic AKI, constituting an important advance for optimizing septic AKI animal models.