TH and stroke disorder: To investigate whether the motor deficits, which TgM83+/− mice displayed beginning at 180 days after stroke, may have been caused by a loss of dopaminergic neurons in the substantia nigra, we stained midbrain tissue sections of animals sacrificed at 14, 30, 90, 180, and 360 days post surgery with an antibody to tyrosine hydroxylase (TH) (Fig. 4a).