The aim of this study was to determine the effectiveness of cortisol, interleukin (IL)-6, C-reactive protein (CRP), and white blood cell (WBC) count as inflammatory markers to evaluate the postoperative inflammatory response associated with various abdominal surgical procedures in rats. Wistar albino rats (N=152) were randomly assigned to 7 groups: control, hepatectomy, splenectomy, nephrectomy, colectomy, gastrectomy, and sham. Apart from the control group, each group was then divided into 3 subgroups: 6th, 24th and 48th h. Thus, a total of 19 groups were defined, each including 8 rats. At the 6th, 24th and 48th h following the surgical procedures blood samples from each rat were collected. The plasma concentrations of IL- 6, cortisol, CRP, and WBC were measured. Both the surgery category and the elapsed time after the surgery had a significant effect on IL-6 levels (P<0.0001). Blood CRP levels were primarily determined by the surgery category (P<0.0001). Neither surgery nor the elapsed time had a significant effect on the cortisol levels. The elapsed time after surgery was the major factor that influenced the differences in WBC count among the surgery groups (P<0.0001). Our results cumulatively indicate that the levels of IL-6, CRP, and cortisol and WBC count change at different time points after several abdominal surgical procedures. Cortisol level is not related to the type of surgical procedure or the elapsed time, while WBC count decreases with the elapsed time. None of the changes in the markers investigated in this study is specifically related to the category of abdominal surgical procedure. Copyright: © Hellenic Society of Gastroenterology.