Minimal Motor Impairment (rat)
In rats, minimal motor impairment (MMI) is indicated by ataxia, which is manifested as an abnormal, uncoordinated gait. In addition to MMI, animals may exhibit a circular or zigzag gait, abnormal body posture and spread of the legs, tremors, hyperactivity, lack of exploratory behavior, somnolence, stupor, catalepsy, loss of placing response, and changes in muscle tone. Animals are visually evaluated, and a rat is considered impaired if it displays two or more of these abnormal behaviors. Assessment for impairment is usually performed on the same animals in conjunction with seizure models.
Quantification of the dose that induces toxicity in 50% of animals treated with the compound (TD50) is conducted at the time of peak effect (TPE) and is described separately.