[The effect of perftoran on the resistance of mice to GABA receptor antagonists and on the antidote activity of anticonvulsant agents]. / Vliianie perftorana na ustoichivost' myshei k antagonistam GAMK-retseptorov i antidotnuiu aktivnost' protivosudorozhnykh sredstv.

Perfluorane (a phenobarbital-type inducer of the microsomal enzyme system) raised the resistance of mice to the toxic effect of picrotoxin and bicucullin in 7 days after injection. The antidote effect of diazepam and phenobarbital increased under such conditions. In experiments in vitro a modulatory effect of perftorane on the central muscarine and benzodiazepine receptors was demonstrated.

[The effect of 3-mercaptopropionic acid on the toxicity of GABA-lytics for mice]. / Vliianie 3-merkaptopropionovoi kisloty na toksichnost' GAMK-litikov dlia myshei.

The influence of 3-mercaptopropionic acid (3-MPA) on toxicities of bicuculline and picrotoxin was evaluated in mice. It was demonstrated that 3-MPA pretreatment for 5 min increased the toxicities of bicuculline and picrotoxin by 26% and 31%, respectively. 3-MPA did not alter the binding of (3H)TBOB and (3H)GABA to synaptosomal brain membranes of intact mice. The changes in toxicity may be associated with increased binding of GABA-antagonists to their receptors due to decreased brain GABA.

[The effect of triorthocresyl phosphate on the toxicity of GABA-lytics for mice]. / Vliianie triortokrezilfosfata na toksichnost' GAMK-litikov dlia myshei.

The toxicity of the picrotoxin bicuculline, but not of 3-mercaptopropionic acid increased in mice pretreated with triorthocresyl phosphate (TOCP). TOCP decreased the affinity of brain GABA receptors of intact mice for [3H] GABA. The binding of [3H]-t-butylcycloorthobenzoate was unchanged. The increased toxicity of GABA-antagonists may be associated with inhibition of blood carboxylesterases. The possibility of direct influence of TOCP and its metabolites on the GABA/benzodiazepine receptor complex cannot be excluded.

[N-methyl-3H]methylphenazepam--a new ligand for benzodiazepine receptors]. / [N-metil-3H]metilfenazepam--novyi ligand dlia benzodiazepinovykh retseptorov.

The binding of [N-methyl-3H] methylphenazepam with synaptosomal membranes of rat striatum was studied. The affinity of binding sites to this ligand was higher when compared with [3H] diazepam. No changes in maximal binding capacity were found in two groups. GABA and muscimol increased the binding of [3H] diazepam and had no effect on binding of [N-methyl-3H] methylphenazepam. Diazepam and phenazepam competitively decreased the [N-methyl-3H] methylphenazepam binding. The inhibitor activity of phenazepam was higher.

[Effects of diisopropylfluorophosphate, paraoxon and dichlophos on [3H] quinuclidinyl benzylate binding to the rat striatum synaptic membranes]. / Vliianie diizopropilftorfosfata, paraoksona i dikhlofosa na sviazyvanie [3H] khinuklidinil benzilata s sinapticheskimi membranami striatuma krys.

The binding of [3H] quinuclidinyl benzilate (QNB) to rat striatum membranes after diisopropylfluorophosphate (DFP) induced seizures was characterized. There was a 36% decrease in Kd and a 33% decrease in the number of muscarinic receptors. Paraoxon caused inhibition fo [3H] QNB binding to the striatal membranes of intact rats. It is possible that a direct action of DFP on the muscarinic receptor is not the cause of anti-cholinesterase-induced changes in [3H] QNB binding.