Influence of ozonized saline on behaviors of rat models with incisional pain and levels of plasma TNF-α and IL-6

Abstract

Objective To investigate the analgesia effect and the possible mechanism of intravenous administration with different concentrations of ozonized saline (OS) by observing changes in behavior, plasma tumor necrosis alpha (TNF-α), and interleukin-6 (IL-6) levels after rat plantar incision. Methods Fifty-four health adult male Sprague-Dawley rats were used in the investigation. Twenty four rats were randomly divided into four groups, 6 in each group. The rats in group A1 were intravenously administered with 5ml/kg oxygen saline, 10min before the incision. The rats in groups B1, C1, and D1 were intravenously administered with 20 μg/ml, 30 μg/ml, and 40 μg/ml OS 5 ml/kg. An 1-cm incision was made in the right plantar surface from the heel to the toes according to the method described by Brennan under sevoflurane anesthesia. The 50% paw withdrawal mechanical threshold (50% PWMT) and cumulative pain score (CPS) at the times of 24 h before and 2, 6, 24, 48 h after surgery were underwent. Thirty rats were randomly divided into five groups, 6 in each group. Groups A2, B2, C2, and D2 processed as well as group 1. All groups except group E2 were made the model of incisional pain. 2 ml blood was taken out of the right ventricular 2 h after the operation, then the levels of plasma TNF-α and IL-6 were detected by using enzyme linked immunosorbent assay (ELISA). Results There were no significant differences in the 50% PWMT between group A1 and group B1 at each time point after surgery (P>0.05). The 50% PWMT in groups C1 and D1 were higher than those in group A1 at each time point after surgery (P 0.05). The levels of plasma TNF-α in groups C2 and A2 were higher than those in group E2(P 0.05). The levels of plasma IL-6 in groups B2, C2, and D2 were higher than those in group E2 (P<0.05). Conclusions Intravenous administration of ozonized saline can inhibit the incisional pain in rats. The analgesia effect of ozonized saline was dose-dependent. Key words: Ozone/PD; Pain, postoperative/DT/ME; Tumor necrosis factor-alpha/ME; Interleukin-6/ME