Immunocytochemical study by two photon fluorescence microscopy of the distribution of GABAA receptor subunits in rat cerebellar granule cells in culture

• Published in: Amino acids Vol. 26; no. 1; pp. 77 - 84
• Main Authors: Merlo, F, Balduzzi, R, Cupello, A, Robello, M
• Format: Journal Article
• Language: English
• Published: Springer-Verlag 01.02.2004
• Subjects: cerebellum; cytoplasm; fluorescence microscopy; neurites; plasma membrane; rats
• ISSN: 0939-4451; 1438-2199
• DOI: 10.1007/s00726-003-0006-z

An immunocytochemical investigation of the expression of α₁, α₆, β₂/₃, γ₂and δ subunits was performed on rat cerebellum granule cells in culture by the two photon microscopy technique.The first four subunits appear to be expressed abundantly in these cells, whereas the δ one seems to be expressed at a lower level. Another major difference in the distribution of these subunits is that whereas α₆, β₂/₃and γ₂appear only on plasma membranes α₁and δ are present mainly in the cell bodies cytoplasm. Still another difference was found in that the presence of γ₂on neurites is “polarized”, preferentially labelling neurites with the appearance of dendrites. The subunits α₆and β₂/₃appear to label all types of neurites, with β₂/₃being by far the most heavily expressed subunit type. A final distinct characteristic is that α₆and, even more, γ₂appear to accumulate in the cytoplasmic domains immediately below the cone of emergence of neurites. This suggests a conspicuous transport of such subunits from the site of synthesis in the cell body to the site of final expression in the neurites (dendrites and axon terminals).