Effects of dopamine depletion on rotational behavior to dopamine agonists.

The contralateral rotation to various dopamine agonists was determined in rats with unilateral lesions of the left nigrostriatal pathway both with and without dopamine depletion caused by dopamine synthesis inhibition. The rotation to drugs possessing D-2 dopamine agonist activity alone was greatly diminished by dopamine depletion. In contrast, the rotation induced by drug possessing D-1 dopamine agonist activity (either D-1 alone or D-1 plus D-2) was affected to a much lesser extent by dopamine depletion.