Figure 2.

Localization of POP in different neuronal cell types in the central nervous system. Based on the neuroanatomy and colocalization studies, POP is present in glutamatergic, γ-aminobutyric acid (GABA)ergic, and cholinergic systems. Red dots indicate the presence of POP. Moreover, POP is evidently located in the thalamocortical/corticothalamic projection neurons between VP/VM and M1/S1 and Aud1/MGN. POP is also believed to be localized in the projection neurons between V1-cortex and LGN and GABAergic neurons of the nigrostriatal path (dashed line). Aud, primary auditory cortex; Fr, frontal cortex; Hc, hippocampus; LS/IG, lateral septum/indusium griseum; M1/S1, primary motor/somatosensory cortex; MGN, medial geniculate nucleus; LGN, lateral geniculate nucleus; SN, substantia nigra; VP/VM, ventrobasal/ventromedial thalamic nuclei; V1, primary visual cortex.