The effects of diclofenac sodium on cold water swim induced analgesia

Abstract

It was clearly demonstrated that cold water swimming induces analgesia in mice and rats; produced by opioid and non-opioid mechanisms. Aim of this study is to determine the effect of diclofenac sodium (DS) on this phenomenon. 60 Swiss Webster strain albino male mice (average weight 25-35 gr) was investigated ethic committee approval. Animals were separated into four equal group in a randomised fashion. Normal saline (Control: C) was given to the 1st group, naloxone (NL) 100 mg/kg was given to the 2nd group, diclofenac sodium (DS) 2 mg / kg was given to the 3rd group and diclofenac sodium 2 mg/kg with naloxone 100 ?gr / kg (DS+NL) to the 4th group of animals 7 minutes before cold water swim stress (CWSS) test at same volume (0.1 ml) by intraperitoneal (IP) route. CWSS was performed at 10°C water for 3 minutes. Animals were taken to the separate chamber and dried gently. Hot plate test (HPT) at 56°C was performed 10 minutes later. Animals were exposed to HPT maximal 20 seconds to prevent tissue injury. Characteristic fore limb licking, hind limb shaking or withdrawal were taken as positive result. Data were expressed as mean ± standard deviation of mean (Mean ± SD). Analyses of variance (ANOVA), student's t test and Mann-Whitney u test were used for statistical analyses. P<0.05 was taken as significant. There were no differences between groups on basal temperature. Also, no differences were found between HPT results on C and DS; NL and DS+NL treated animals. In comparison significant differences were found between C and DS groups with NL and DS+NL given animals (p<0.05). Regarding to these results there were no additional effects of DS on CWSS analgesia at given doses. This analgesia decreased by NL and doesn't change by DS. Study design will be constructed and directed to the tonic pain models.