摘要：

547o891.2)-06:612o821.3 A study of the behavior of inbred animals under conditions of emotional stress, of the biochemical parameters of the stress reaction, and effects of benzodiazepine tranquilizers, conducted in the writers' laboratory showed that the character of the response to stress and manifestation of the action of BD depend on hereditary factors (3). The aim of this investi- gation was to study reception of SH-diazepam by brain cell membranes of C57BL/6 (B/6) and BALB/c (B/c) mice, which were used as models in the previous investigations. EXPERIMENTAL METHOD Experiments were carried out on male B/6 ahd B/c mice weighing 18-20 g. The animals were kept in the laboratory animal house for at least 2 weeks before the beginning of the experi- ments, on a standard diet, with I0 mice per cage, and with alternation of 12 h daylight and 12 h darkness. To study binding of 3H-diazepam (specific activity 71 Ci/mmole, Amersham International, England) the mice were decapitated and the brain quickly removed, the brain stem and cere- bellum were detached, and the remainder was homogenized in 25 ml of 50 mM Tris-citrate buf- fer, pH 7.4, and centrifuged at 45,000g for 25 min of an L5-50 ~entrifuge (42.1 rotor, Beck- man, USA). The residue was resuspended by rehomogenization in the same volume of buffer, and then centrifuged again. The washing procedure was repeated 3 times and the resulting residue resuspended in 70 ml of Tris-citrate buffer and used in a volume of 1 ml in experiments to study binding of 3H-diazepam, which was added to the medium in a final concentration of 1 nM~ In the series of experiments with previously frozen preparations, the residue was resuspended in the minimal volume of buffer and frozen for 24 h at --20~ The sample was thawed and homogenized by centrifugation for 25 min at 45,000g, and then washed once. X~e residue was resuspended in 70 ml of buffer and used in radioligand binding experiments. The protein con- tent in the samples was 150-200 ~g. Nonspecific binding was determined in the presence of i0 DM unlabeled diazepam. Incubation was carried out for 30 min at 0~ and the reaction was stopped by rapid filtration through a GF/B filter (Whatman, England), followed by washing twice with cold buffer solution. The filters were placed in scintillation fluid: toluene-- ethanol 7:3 by volume in the presence of 0.4% PPO and 0.01% POPOP). RadioaCtivity was mea- sured on an LS-100C counter (Beckman). The counting efficiency was 45%. Protein was deter- mined by a modified Lowry's method. The results were subjected to statistical analysis by Student's test~

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