Effects of androsterone on convulsions in various seizure models in mice.

It is believed that a deficiency of androgens, including free testosterone, may promote the development of convulsions. The present study revealed differences in the action of androsterone (AND), a major excreted metabolite of testosterone and a neurosteroid, in three commonly used seizure models in mice. AND administered intraperitoneally exhibited dose-dependent protection against tonic-clonic convulsions caused by maximal electroshock (MES) with ED(50) (effective dose(50)) of 227 mg/kg. The compound also inhibited the convulsive action of pentylenetetrazole (PTZ), increasing its CD(50) (convulsive dose(50)) for clonic convulsions from 77.2 (PTZ + saline) to 93.9 (p < 0.05) for PTZ + AND 40 mg/kg and 113.9 mg/kg (p < 0.001) for PTZ + AND 60 mg/kg. In mice pretreated with 60 mg/kg AND, the CD(50) for PTZ-induced tonic convulsions increased from 102 to 127.6 mg/kg (p < 0.01). Surprisingly, doses of 50 and 100 mg/kg AND lowered the CD(50) for kainate (KA)-induced convulsions from 40.8 to 28.7 (p < 0.05) and 25.4 mg/kg (p < 0.001), respectively. In summary, for two of the mouse seizure models, our findings confirmed previous studies that demonstrated protective activity of AND. However, the potentiation of KA-induced convulsions by AND was somewhat unexpected and suggested that AND may also possess proconvulsant activity.