Table 3. Studies reporting myelination of parvalbumin-expressing interneurons.
Study | Species | Brain region | Technique | Conclusion |
---|---|---|---|---|
Micheva et al.125 | Mouse | Somatosensory cortex | Array tomography; electron microscopy; immunofluorescence | ~25–50% of myelinated axons in the neocortex are GABAergic, of which nearly all are PV+ |
McGee et al.97 | Mouse | Visual cortex | Immunofluorescence | ~One-third of myelinated axons are PV+ |
Somogyi et al.98 | Cat | Visual cortex | Electron microscopy | Presence of several myelinated basket cells |
Somogyi et al.99 | Cat | Visual cortex | Electron microscopy | Presence of two myelinated basket cells |
Chung et al.101 | Human | Frontal cortex | Immunofluorescence (CLARITYa) | Single figure of myelinated PV axons |
Seress et al.103 | Human | Hippocampus | Electron microscopy | Presence of a few myelinated PV axons |
Hinova-Palova et al.104 | Human | Claustrum | Electron microscopy; Immunofluorescence | Presence of several myelinated PV axons |
Peters et al.112 | Rat | Visual cortex | Electron microscopy | Presence of several myelinated basket cells |
Wouterlood et al.119 | Rat | Entorhinal cortex | Electron microscopy | Extensive presence of myelinated PV axons throughout all cortical layers |
Gartner et al.115, 116;Brauer et al.124 | Rat | Hippocampus | Immunofluorescence; electron microscopy | Majority of septohippocampal PV fibers show myelination, but not cholinergic ones |
Kita et al.123 | Rat | Neostriatum | Electron microscopy; light microscopy | Presence of several myelinated PV neurons |
Freeman et al.117 | Rat | Hippocampus (in vitro) | Hippocampal cultures; immunofluorescence | Myelination of PV neurons in vitro |
Katsumaru et al.122 | Rat | Hippocampus | Electron microscopy | Presence of myelinated PV neurons |
Hu et al.151 | Rat | Hippocampal dentate gyrus | Immunofluorescence | No myelinated PV fibers present |
Abbreviations: GABA, gamma-aminobutyric acid; PV, parvalbumin.
CLARITY (Chung et al.100) is a recently developed technique which enables immunofluorescence-based labeling and imaging of large volumes of structurally intact, optically transparent tissue.