Hyperbaric oxygen (HBO2) therapy reportedly reduces opiate withdrawal in human subjects. The purpose of this research was to determine whether HBO2 treatment could suppress physical signs of withdrawal in opiate-dependent mice. Male NIH Swiss mice were injected s.c. with morphine sulfate twice a day for 4 days, the daily dose gradually increasing from 50 mg/kg on day 1 to 125 mg/kg on day 4. On day 5, withdrawal was precipitated by i.p. injection of 5.0 mg/kg naloxone. Mice were observed for physical withdrawal signs, including jumping, forepaw tremor, wet-dog shakes, rearing and defecation for 30 min. Sixty min prior to the naloxone injection, different groups of mice received either a 30-min or 60-min HBO2 treatment at 3.5 atmospheres absolute. HBO2 treatment significantly reduced naloxone-precipitated jumping, forepaw tremor, wet-dog shakes, rearing and defecation. Based on these experimental findings, we concluded that treatment with HBO2 can suppress physical signs of withdrawal syndrome in morphine-dependent mice.
Categories: Medical clinic, Toxicology