NDP and Huntington disease: The presence of very densely labelled (hyperchromic) degenerated/shrunk cortical (primarily pyramidal) neurons—demonstrated also by other histological staining methods—unequivocally confirms that, in tgHD51 rats, NDP in the striatum is accompanied with the degeneration of cortical neurons (Figures 8(f) and 8(g)) alike in human HD brain.