Effect of a GABA agonist on the expression and distribution of GABAA receptors in the plasma membrane of cultured cerebellar granule cells: an immunocytochemical study

TY - JOUR

T1 - Effect of a GABA agonist on the expression and distribution of GABAA receptors in the plasma membrane of cultured cerebellar granule cells: an immunocytochemical study

AU - Hansen, Gert Helge

AU - Belhage, B

AU - Schousboe, A

N1 - Keywords: Animals; Cell Membrane; Cells, Cultured; Cerebellum; Immunohistochemistry; Isoxazoles; Rats; Receptors, GABA-A; gamma-Aminobutyric Acid

PY - 1991

Y1 - 1991

N2 - The effect of the gamma-aminobutyric acid (GABA) agonist 4,5,6,7-tetrahydroisoxazolo[5,4-c]pyridin-3-ol (THIP, 150 microM) on the localization and density of GABAA receptors in the plasma membrane of rat cerebellar granule cells in primary cultures was studied at the electron microscope (EM) level by preembedding immunogold staining using the monoclonal antibody bd-17 directed against the beta-subunit of the GABAA receptor complex. In THIP-treated as well as untreated control cultures, GABAA receptors were found to be evenly distributed in the plasma membrane of cell bodies as well as processes. However, the density of the GABAA receptors was significantly increased in the THIP-treated cultures as compared to the control cultures and this effect of THIP was particularly pronounced in the processes. GABAA receptors were occasionally observed to form 'hot spots' in process-like structures and again the frequency of these areas with an extremely high density of GABAA receptors was greatly increased in the THIP-treated cultures compared to the controls. It has thus been demonstrated that the ability of GABA agonists to induce formation of low-affinity GABA receptors can be directly visualized and quantified at the EM level using the preembedding immunogold technique. It is likely that low-affinity GABAA receptors are preferentially located in the cell processes and to a considerable extent in the form of 'hot spots'. However, these 'hot spots' also contain high-affinity receptors.

AB - The effect of the gamma-aminobutyric acid (GABA) agonist 4,5,6,7-tetrahydroisoxazolo[5,4-c]pyridin-3-ol (THIP, 150 microM) on the localization and density of GABAA receptors in the plasma membrane of rat cerebellar granule cells in primary cultures was studied at the electron microscope (EM) level by preembedding immunogold staining using the monoclonal antibody bd-17 directed against the beta-subunit of the GABAA receptor complex. In THIP-treated as well as untreated control cultures, GABAA receptors were found to be evenly distributed in the plasma membrane of cell bodies as well as processes. However, the density of the GABAA receptors was significantly increased in the THIP-treated cultures as compared to the control cultures and this effect of THIP was particularly pronounced in the processes. GABAA receptors were occasionally observed to form 'hot spots' in process-like structures and again the frequency of these areas with an extremely high density of GABAA receptors was greatly increased in the THIP-treated cultures compared to the controls. It has thus been demonstrated that the ability of GABA agonists to induce formation of low-affinity GABA receptors can be directly visualized and quantified at the EM level using the preembedding immunogold technique. It is likely that low-affinity GABAA receptors are preferentially located in the cell processes and to a considerable extent in the form of 'hot spots'. However, these 'hot spots' also contain high-affinity receptors.

M3 - Journal article

C2 - 1648687

SN - 0167-6253

VL - 124

SP - 162

EP - 165

JO - Neuroscience letters. Supplement

JF - Neuroscience letters. Supplement

IS - 2

ER -