Medical herb Mongolian astragalus has anxiolytic activity in conflict situation imposed on random-bred male albino rats, and evokes changes in electroencephalogram which are characteristic of tranquilizers. The drug moderates the x-rhythm in cerebral hemispheres and hippocampus. In contrast to benzodiazepine tranquilizers, it does not affect the frequencies in other bands. Key Words: medical herbs; anxiolytic effect; conflict situation; electroencephalogramMedical herbs are widely used in the therapy of neurotic and borderline-neurotic states as sedative [4] and supporting [2] preparations. Since the drugs used in the treatment of these diseases produce unfavorable side-effects, some medical herbs may be prospective as minor daytime tranquilizers. This paper deals with anxiolytie effect of Mongolian astragalus (MA), which is a herb of the leguminous family growing in Russia and Mongolia. The mechanism of MA action was examined by analysis of changes in the electroencephalogram (EEG). MATERIALS AND METHODSThe study was carried out on random-bred male albino rats weighing 200-250 g.Anxiolytic activity was examined on the model of conflict situation based on antagonism (conflict) of drinking motivation and electrical noeieeptive stimulation [12]. The study used a multichamber setup developed at the Laboratory of Psyehopharmacology of the Institute of Pharrnaeology, Russian Academy of Medical Sciences [6]. After deprivation and conditioning to drink from a drinking bowl, the rats were arbitrary subdivided into the following groups: nonpunished control group, in which rats were given distilled water with no electrical current Institute of Pharmacology, Ru~nn Academy of Medical Sciences, Moscow; Institute of Folk Medicine, Ulan-Bator applied to the drinking bowl (this group was used to estimate motor activity and drinking motivation on the day of experiment); punished control group, in which rats were given water, but electrical current was applied to the drinking bowl; three groups of rats, in which MA was administered in increasing doses; and three groups of rats, in which increasing doses of phenazepam (a control drug) were given. The effect was evaluated by statistically significant increase in the number of punished water takings in the control group rats in comparison with the punished control group at an electrical current strength of 0.5 or 1 mA. The effects of preparations on motor activity were assessed visually by the number of erossings of the lines, which were drawn on the floor under the electrode wires spaced at 5 cm [5].The EEG was recorded under unrestrained behavioral conditions from the rats in which Nichrome electrodes were implanted into the hippocampus and frontal cortex under local anesthesia and Nembutal narcosis (40 mg/kg). The reference electrode was fixed in the nasal bones. On postoperative days 7-10 (restoration period surgery operation and narcosis) the EEG was recorded with the help of a Neurograph 18-channel electroencephalograph (O.T.E. Biomediea), with amplifiers tuned for the standard...

Tranquilizers of the benzodiazepine group, albeit widely used in clinical practice, are known to exhibit a number of side effects (myorelaxant, sedative, and amnesic) and have a risk of inducing a drug dependence. For this reason, there is continuing search for alternative, more safe tranquilizers producing "soft" anxiolytic action. In particular, some medicinal plants may serve as such tranquilizers. These preparations are usually administered as sedative agents [1], although the question as to whether they also possess a tranquilizer and antidepressant activity requires additional investigation.The purpose of this work was to study the anxiolytic and antidepressant properties and possible side effects of some medicinal herbs occurring in Russia and Mongolia.In this park we have studied the effects of astragalus mongolensis (fabaceous family), allium odoratum (liliaceae family), paeonia anomala (Ranunculaceae family), and patrinia montana (valeriana family). The maximum activity was observed for the plants of astragal; therefore, preparations of this plant were studied in more detail. EXPERIMENTAL PARTExperiments were performed on a group of white mongrel male rats weighing 200 -250 g.The anxiolytic activity of the medicinal plant preparations was studied using a model of conflict situation (drinking motivation versus electroshock pain irritation) and evaluated by monitoring the number of penalized water takes from a dish at an electric current strength of 0.5 or 1 mA [2,3]. The reference drug was the well-known tranquilizer phenazepam.The antidepressant action of the astmgal preparations was evaluated by measuring the number of turns of a wheel rotated by rats in a swimming pool [4], the test being modified as described in [5]. The effect of the plant preparation was compared to the action of amitriptylin (antidepressant) and caffeine (psychostimulator).