Effects of MPTP on locomotor activity in mice.

Thirty-two mice were randomly assigned to one of 4 groups of 8 animals each: the first received IP saline injections and the other 3 groups received 10, 20 or 30 mg/kg MPTP. Each dose or saline was administered 3 times in 3 consecutive days and locomotor activity was measured during the next 3 days. In addition, the animals were observed in 2 trials in a rotating rod (Rotarod) and a grip test. The 2 highest doses of the drug produced significant increases in locomotor activity. In the other two behavioral tests, the highest dose of MPTP significantly reduced the capability of the animals to remain on the Rotarod on the grid.