A novel recognition site for somatostatin-14 on the GABA(A) receptor complex.
Functional interactions between gamma-aminobutyric acid (GABA) and somatostatin are suggested by the presence of synaptic contacts between GABA and somatostatin neurons, colocalisation of GABA and somatostatin and reciprocal modulation of somatostatin and GABA release. Nevertheless, a direct interaction of somatostatin with the GABA(A) receptor complex has not yet been investigated. A quantitative autoradiographic technique was used to determine the ability of somatostatin to interact with the [35S]t-butylbicyclophosphothionate [35S]TBPS binding sites of the GABA(A) receptor complex: somatostatin inhibited [35S]TBPS binding with IC50 values in the micromolar range in all brain regions studied. These results demonstrate for the first time a direct interaction between somatostatin and the GABA(A) receptor complex.
Vincens
M
M
Pharmacologie Endocrinienne, Université Paris VII, Hopital Lariboisière, France.
Mauvais-Jarvis
F
F
Behar
S
S
D000818:Animals; D001665:Binding Sites; D019086:Bridged Bicyclo Compounds, Heterocyclic / Q000378:metabolism; D008636:Mesencephalon / Q000378:metabolism; D011869:Radioligand Assay; D051381:Rats; D011963:Receptors, GABA-A / Q000378:metabolism*; D013004:Somatostatin / Q000378:metabolism*; D013462:Sulfur Radioisotopes
D019086:Bridged Bicyclo Compounds, Heterocyclic; D011963:Receptors, GABA-A; D013462:Sulfur Radioisotopes; D013004:Somatostatin; C037476:tert-butylbicyclophosphorothionate