Antinociceptive effects of magnesium sulphate alone and along with Gabapentin on crack Withdrawal time caused Hyperalgesia

Crack withdrawal induced neuropathic pain is common problem among addicted patients particular adolescent due to less tolerance to pain. The patients suffer from lack of effective medication on withdrawal-related pain during bed time.We aimed to consider the antinociceptive effect of Gabapentin(G)and magnesium sulfate(M)on crack withdrawal hyperalgesia .Since this pain is one of the most deadly pain, Therefore, based on this investigation,veterinarian can use these prescription in order to reduce the pain specially in the horse.Thirty male wistar rats (weight 250 ± 20) were involved in study and equally divided into five groups: To induce withdrawal hyperalgia, Versus one group normal saline control(S) Four groups were continually received crack (0.97mg/kg,C) for thirty days followed by intraperitonealy receiving either normal saline (0.09%,CS), Gabapentin (CG,300 mg/kg), magnesium sulfate ( CM, 50 mg/kg),or Gabapentin (300 mg/kg) +magnesium sulfate (CGM,50mg/kg). 24 hours after the last administration of crack, Hot plate test were applied for the investigation of central antinociceptive activity. Measurements were obtained at time points: before treatment (baseline) and 15, 30, 45, 60,75 and 90 minutes after peritoneal injection of drugs. Brain PGE2 was measured by ELISA Due to induction of tolerance, Thirty days crack administration revealed a important decrease in Maximal potent effect (%MPE) (p 0.05) in(C)compare to normal control group(S).24 hours after the last administration of crack,receiving of antinociceptive drugs showed a significant(p 0.05) increase trend in %MPE in both CG and CM alone in compare CS.Combination of two drugs has no synergic effect on hyperalgia versus CG (P= 0.23) or CM (p=0.31) alone.The highest %MPE was observed in 45th and 60thminutes after injection for Gabapentin or MgSO4 respectively.Brain PGE2 was significantly (p 0.05) decreased in both CG an CM versus CS. Antinociceptive effects of gabapentin and magnesium sulfate may be able