Article date: 1987/3/1
PubMed ID: 3027258
Journal name: Journal of neurochemistry (ISSN: 0022-3042)
The binding of [35S]t-butylbicyclophosphorothionate ([35S]TBPS), a gamma-aminobutyric acid (GABA)-activated chloride ionophore ligand; [3H]diazepam, a benzodiazepine agonist; and [3H]muscimol, a GABA receptor probe, were used to assess the effects at 100 microM of deltamethrin, dichlorodiphenyltrichloroethane (DDT), and three experimental insecticides–a DDT-pyrethroid hybrid, GH414 (cycloprothrin), and two DDT-analogues, GH266 and GH149 (EDO), on GABA receptor ionophore complexes in a rat brain membrane preparation. GH266 and GH149 were found to inhibit a greater percentage of [35S]TBPS binding than the same concentration of deltamethrin or DDT, although GH414 had little effect. GH266 and GH149 enhanced [3H]diazepam binding by nearly 200%, in contrast to the inhibitory effects of deltamethrin, DDT, and GH414. GH266 and GH149 also caused a dramatic enhancement of [3H]muscimol binding, 367 and 236% of control, respectively, whereas DDT and deltamethrin caused only a moderate enhancement. The effects of the insecticides on binding affinity and density were examined for each of the ligands. The results show a differential interaction of the insecticides on the various ligand binding sites.
Author List: Lummis S C, Chow S C, Holan G, Johnston G A
Publication Types: Comparative Study; Journal Article; Research Support, Non-U.S. Gov't
Substances mentioned in the article: Bridged Bicyclo Compounds; Bridged Bicyclo Compounds, Heterocyclic; Insecticides; Ionophores; Nitriles; Pyrethrins; Receptors, GABA-A; Muscimol; decamethrin; tert-butylbicyclophosphorothionate; DDT; Diazepam;
Mesh terms: Animals; Brain/metabolism; Bridged Bicyclo Compounds/metabolism; Bridged Bicyclo Compounds, Heterocyclic; Cell Membrane/metabolism; DDT/analogs & derivatives; Diazepam/metabolism; Insecticides/pharmacology; Ionophores/metabolism; Male; Muscimol/metabolism; Nitriles; Pyrethrins/pharmacology; Rats; Rats, Inbred Strains; Receptors, GABA-A/drug effects;