Treatment with zolpidem after ethanol administration potentiates the expression of ethanol-induced behavioral sensitization in mice.

Contradictory findings suggest that the behavioral and abuse-related effects of ethanol are mediated by its action at α1 subunit-containing GABAA (α1GABAA) receptors. In the present study, we investigated the effects of a sub-chronic post-ethanol administration treatment with zolpidem, an α1-preferring positive allosteric modulator at GABAA receptors, on the subsequent expression of ethanol-induced behavioral sensitization in mice. Animals received ethanol (1.8 g/kg, ip) or saline treatments every other day for 15 days (8 treatment sessions) and were subsequently treated with zolpidem (0.5 mg/kg, ip) or vehicle 4 times on alternate days. At the end of the treatment phase, animals were challenged with saline or ethanol on separate days for the evaluation of the expression of conditioned locomotion and behavioral sensitization. Eight-day treatment with ethanol did not lead to the development of ethanol-induced behavioral sensitization. Animals treated with ethanol and subsequently administered vehicle showed similar locomotion frequencies during the last ethanol challenge compared to the control group receiving ethanol for the first time. Animals treated with ethanol and subsequently administered zolpidem expressed behavioral sensitization to ethanol during the ethanol challenge. The present study adds to the literature by providing further evidence of a role of α1GABAA receptors on the behavioral effects of ethanol. Because of the current highly prevalent co-abuse of ethanol and benzodiazepine drugs in humans, the use of zolpidem and other α1GABAA receptor ligands during ethanol withdrawal should be monitored carefully.

Treatment with zolpidem after ethanol administration potentiates the expression of ethanol-induced behavioral sensitization in mice

Contradictory findings suggest that the behavioral and abuse-related effects of ethanol are mediated by its action at α1 subunit-containing GABAA (α1GABAA) receptors. In the present study, we investigated the effects of a sub-chronic post-ethanol administration treatment with zolpidem, an α1-preferring positive allosteric modulator at GABAA receptors, on the subsequent expression of ethanol-induced behavioral sensitization in mice. Animals received ethanol (1.8 g/kg, ip) or saline treatments every other day for 15 days (8 treatment sessions) and were subsequently treated with zolpidem (0.5 mg/kg, ip) or vehicle 4 times on alternate days. At the end of the treatment phase, animals were challenged with saline or ethanol on separate days for the evaluation of the expression of conditioned locomotion and behavioral sensitization. Eight-day treatment with ethanol did not lead to the development of ethanol-induced behavioral sensitization. Animals treated with ethanol and subsequently administered vehicle showed similar locomotion frequencies during the last ethanol challenge compared to the control group receiving ethanol for the first time. Animals treated with ethanol and subsequently administered zolpidem expressed behavioral sensitization to ethanol during the ethanol challenge. The present study adds to the literature by providing further evidence of a role of α1GABAA receptors on the behavioral effects of ethanol. Because of the current highly prevalent co-abuse of ethanol and benzodiazepine drugs in humans, the use of zolpidem and other α1GABAA receptor ligands during ethanol withdrawal should be monitored carefully.

Effects of ayahuasca on the development of ethanol-induced behavioral sensitization and on a post-sensitization treatment in mice.

BACKGROUND: Hallucinogenic drugs were used to treat alcoholic patients in the past, and recent developments in the study of hallucinogens led to a renewal of interest regarding the application of these drugs in the treatment of addiction. In this scenario, accumulating evidence suggests that the hallucinogenic brew ayahuasca (Aya) may have therapeutic effects on substance abuse problems. METHODS: We investigated the effects of Aya on spontaneous locomotor activity and ethanol(Eth)-induced hyperlocomotion and subsequent locomotor sensitization by a two-injection protocol. Additionally, we tested the effect of Aya on an 8-day counter-sensitization protocol to modify sensitized responses induced by a repeated treatment with Eth (1.8g/kg) for 8 alternate days. RESULTS: Aya showed high sensitivity in preventing the development of Eth-induced behavioral sensitization, attenuating it at all doses (30, 100, 200, 300 or 500 mg/kg) without modifying spontaneous locomotor activity. At the highest doses (300 and 500 mg/kg), Aya also showed selectivity to both acute and sensitized Eth responses. Finally, a counter-sensitization strategy with 100 or 300 mg/kg of Aya for 8 consecutive days after the establishment of Eth-induced behavioral sensitization was effective in blocking its subsequent expression on an Eth challenge. CONCLUSIONS: We demonstrated that Aya not only inhibits early behaviors associated with the initiation and development of Eth addiction, but also showed effectiveness in reversing long-term drug effects expression, inhibiting the reinstatement of Eth-induced behavioral sensitization when administered in the Eth-associated environment.