Effects of dexmedetomidine on rat locus coeruleus and ethanol withdrawal symptoms during intermittent ethanol exposure

in the present study, the neuroprotective effects of dexmedetomidine on rat locus coeruleus were studied during a B-week intermittent ethanol exposure . Male Wistar rats (3 to 4 months old) were given ethanol or isocaloric suc rose by intragastric intubations three times a day for 4 days, which was fo llowed by a 3-day withdrawal period. This I-day cycle of ethanol exposure a nd withdrawal was repeated five times. Dexmedetomidine (at a dose decreasin g from 30 mu g/kg to 10 mu g/kg, sc) was given to the treatment group durin g the withdrawal phase. The results showed that, during the 5-week experime nt, dexmedetomidine significantly relieved the ethanol withdrawal syndrome, measured as the sum of the three most specific symptoms (rigidity, tremor, and irritability). The total neuron number of locus coeruleus (LC) decreas ed in the ethanol-treated group by 24%, compared with the nontreated contro l group and by 11%, compared with the sucrose-treated control group. Intere stingly, the LC neuron numbers were found to decrease in the sucrose-intuba ted rats as well, compared with the nontreated control group. Dexmedetomidi ne was found to relieve ethanol-induced neuronal loss in the LC. Dexmedetom idine might be a new interesting alternative in the treatment of ethanol wi thdrawal syndrome, particularly due to its possible neuroprotective effects in the central nervous system.