Psychopharmacological profile of the new cognition enhancing agent exifone in the mouse

Hexahydro-2,3,4,3',4',5'-benzophenone (exifone, Adlone), a novel compound proposed for treating cognitive dysfunction in geriatric patients, was tested in a battery of standard psychopharmacological tests in the mouse. The results indicated that the compound was non-toxic and induced no signs of overt stimulation or sedation after acute administration of oral doses up to 1024 mg/kg. The compound was devoid of anxiolytic, anticonvulsant or classical neuroleptic activity and did not antagonize the effects of reserpine or a high dose of apomorphine, two tests indicative of classical antidepressant activity. On the other hand, exifone clearly decreased the duration of immobility in the tail suspension test and antagonized the hypothermia induced by a low dose of apomorphine. The compound shortened the duration of barbital induced sleep without affecting the duration of sleep induced by pentobarbital. The effects observed suggest that exifone is not devoid of psychotropic activity and might possess some properties of an atypical antidepressant.