HIF1A and Parkinson disease: MPTP administration increased the number of HIF-1α+ microglia and HIF-1α+ CD16/32+ microglia in all groups, and increased the number of CD16/32+ microglia in NS/MPTP (PD) and 1xLPS/MPTP (TR PD) groups, but not in the 4xLPS/MPTP (TL PD) group.