The effect of diazepam and of agents which change GABAergic functions in immobility in mice.

When mice are forced to swim a restricted space, they will cease attempts to escape and adopt a characteristic immobile posture. In this study, this immobility was reduced by antidepressants and monoamineoxidase inhibitors. We found that diazepam had the ability to enhance this immobility. It is well known that diazepam exerts its pharmacological effect at least in part through GABAergic functions. Muscimol and aminooxyacetic acid enhanced the immobility. In addition, semicarbazide, bicuculline, picrotoxin and pentylenetetrazol reduced the immobility and pretreatment with bicuculline decreased this enhancement with muscimol, aminooxyacetic acid and diazepam. It seems that GABAergic functions play some role in the mechanism of this immobility.