Bender AS, Hertz L. Pharmacological characteristics of diazepam receptors in neurons and astrocytes in primary cultures.
J Neurosci Res 1987;
18:366-72. [PMID:
2891858 DOI:
10.1002/jnr.490180215]
[Citation(s) in RCA: 30] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Benzodiazepine binding sites in mouse astrocytes and neurons in primary cultures were labeled with [3H]diazepam (1.8 nM), and their inhibition by 14 different benzodiazepines and 3 benzodiazepine antagonists was studied. RO 5-4864, RO 7-3351, and, especially, the antagonist PK 11195 were much more potent in astrocytes than in neurons, whereas the opposite was true for the agonists alprazolam, clonazepam, flurazepam, RO 11-3128, and chlordiazepoxide, and, especially, the antagonists CGS-8216 and RO 15-1788. Flunitrazepam, diazepam, midazolam, RO 11-6893, and RO 5-2181 were about equipotent in the two cell types. The neuronal, but not the astrocytic, binding site showed stereospecificity. In astrocytes most of the drugs had pseudo-Hill coefficients close to one, whereas the pseudo-Hill coefficients in neurons, except for RO 5-4864 and PK 11195, were distinctly lower than one. Thus, the benzodiazepine binding sites had profoundly different pharmacological characteristics in neurons and in astrocytes.
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