Premium
γ‐Aminobutyric Acid Receptor Ionophore Complexes: Differential Effects of Deltamethrin, Dichlorodiphenyltrichloroethane, and Some Novel Insecticides in a Rat Brain Membrane Preparation
Author(s) -
Lummis Sarah C. R.,
Chow Shirley Chen,
Holan George,
Johnston Graham A. R.
Publication year - 1987
Publication title -
journal of neurochemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.75
H-Index - 229
eISSN - 1471-4159
pISSN - 0022-3042
DOI - 10.1111/j.1471-4159.1987.tb05571.x
Subject(s) - deltamethrin , muscimol , ionophore , chemistry , ligand (biochemistry) , binding site , receptor , gaba receptor , gabaa receptor , pyrethroid , biochemistry , pharmacology , biophysics , membrane , biology , pesticide , agronomy
The binding of [ 35 S] t ‐butylbicyclophosphorothionate ([ 35 S]TBPS), a γ‐aminobutyric acid (GABA)‐activated chloride ionophore ligand; [ 3 H]diazepam, a benzodiazepine agonist; and [ 3 H]muscimol, a GABA receptor probe, were used to assess the effects at 100 μ M 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 [ 35 S]TBPS binding than the same concentration of deltamethrin or DDT, although GH414 had little effect. GH266 and GH149 enhanced [ 3 H]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 [ 3 H]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.