A review with many referencesThis report reviews methods of pharmacol. evaluation of drugs for the treatment of patients in the chronic phase of organic brain syndrome including stroke, head injury and senile dementia.The models were developed from the aspects of both species and parameter.In the approach based on species, using middle cerebral artery occluded rats, repeated carotid artery occluded gerbils, internal capsule-lesioned rabbits and rats, head injured rats and senescence accelerated mice (SAM-P/8), impairments of passive learning behavior and EEG, neurol. deficits, and/or neuronal degeneration, which are frequently used as parameters in preclin. study, were observed for a long period after surgical operation or aging.Some cerebral activators such as indeloxazine, Ca-hopantenate, dihydroergotoxine, TSH-releasing hormone (TRH), azetireline (TRH analog) and cytidine diphosphate (CDP)-choline ameliorated these brain dysfunctions.Thus, it was found that brain dysfunction could be observed for a long period in some animal models.However, addnl. parameters corresponding well to clin. events should be observed for evaluating drugs for treatment in the chronic phase.In approach based on parameters, motor (rota rod and traction test) and emotional functions (swimming tests), which have not yet been examined in organic brain syndrome models, were examined in SAM-P/8 mice.Disturbance of brain function in passive avoidance response, forced swimming, rota-rod and traction tests was observed for a long period in SAM-P/8 mice of 8 mo of age, compared with senescence-accelerated-resistant mouse (SAM-R/1).The daily oral administration of calcium channel blockers such as nicardipine and nimodipine once a day for 3 wk ameliorated brain dysfunction in passive avoidance response and rota-rod tests, while amlodipine showed little pharmacol. effect in any.