passages.id: split_6_test_138_passage
passages.type: progene_text
passages.text: The effects of dopamine ( DA ) and its antagonists on the transcallosal activity of pyramidal tract neurons ( PTNs ) and non - PTNs in the anesthetized cat motor cortex were studied with iontophoretic applications ; dopamine , SCH 23390 ( D1 antagonist ) , sulpiride ( D2 antagonist ) and haloperidol .