Acute kidney injury (AKI) is defined as a reduction of renal function in hours, including both structural damage and loss of function. There are limited number of biomarkers for early detection and staging of severity. C-type natriuretic peptide (CNP) has been detected in at several tissues. We aimed to evaluate plasma CNP and creatinine levels correlated with duration of ischemia in an experimentally induced AKI rat model. Forty male Sprague-Dawley type rats (aged 8 to 12 weeks, weighing 250-350 g) were used. The animals were randomly seperated into 4 groups: Group 1(n:10): Only laparotomy was performed. The left renal artery was clamped for 3, 6 and 9 hours in groups 2 ( n:10), 3 (n:10) and 4 (n:10) respectively. CNP and creatinine levels were measured in serum samples from rats. A significant increase in creatinine levels was determined in group 2 according to group 1 (p=0.006). The mean plasma creatinine values in group 3 and 4 were decreased compared to group 2 but this difference was not statistically significant (p=0.0862). The mean CNP level in Group 2 (39.5 ± 7.93 mg/dl) was found numerically higher than group 1 (37.90 ± 5.38mg/dl). There was a statistically insignificant decrease in mean CNP levels in group 3 and 4 compared with group 2. Renal ischemia increases the level of CNP. Although the increase in CNP levels is not significant, it can be said that clinical and experimental studies evaluating the timing of ischemia involving different durations should be performed.
Key words: Acute Kidney Injury, renal ischemia, C-type natriuretic peptide