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On the basis of experimental and clinical studies the authors recommend to use mebikar with promedol in complex with other drugs for the treatment of traumatic shock in the prehospital and hospital periods. It was found to substantially improve results of the antishock therapy.

The tranquilizer mebicar produces an antishock action, normalizes different links of mediator, acid-base and oxygen homeostasis. Mebicar decreases arterial pressure and the tone of peripheral vessels insignificantly and for a short period.

Mebicar, a tranquilizer of the group of tetra-N-alkyl bicyclic bis-ureas, under acute emotional stress in cats (confrontation with a dog), simultaneously with tranquilizing effect on behavior also improves central baroreflex control and reduces hypertensive reaction of the arterial pressure. In rats, it normalizes disorders of individual and intraspecies behavior induced by the stress of a long-term social isolation. It decreases the degree of ulcer injury of the stomach during the immobilization stress.

The effect of mebikar upon the course of traumatic shock was studied on the basis of experimental investigations and clinical observations. The authors have found a positive effect of the drug on indices of acid-base state, histostructure and cellular composition of the liver whose disturbance has a great pathogenetic significance in shock. The application of mebikar considerably improved the results of treatment in clinic and reduced lethality in experiment. It was supposed that the positive effect of the drug was associated with prevention of the development of circulatory disorders and with the maintenance of oxidation-reduction process and the histostructure of tissues.

Under group interaction in cats, a new Soviet tranquilizer mebicar eliminates fear-alarm induced by stimulatin of the emotiogenic zone of the hypothalamus. This action is not associated with myorelaxant or hypnotic action. Mebicar decreases the brain noradrenaline level, exerts no effect on the dopaminergic systems, increases the brain serotonin level, and does not elicit cholinolytic action.

The paper is concerned with studies into the effect of the tranquilizer mebicar, a derivative of tetra-N-alkyl bicyclic bisureas, on the GABA-ergic system. The drug in doses of 250-1500 mg/kg (1/15-1/2 LD50) increased the preconvulsive period upon thiosemicarbazide administration, inconsistently changed the effects of picrotoxin and displayed antagonism in regard to bicucullin. Upon 2-week administration the drug reduced the GABA content in the rat brain. A hypothesis is advanced of mebicar-associated facilitation of the inhibitory GABA-ergic transmission.

It has been shown that the tranquilizers, diazepam (a 1,4-benzodiazepine derivative) and mebicar (a derivative of bicyclic bisureas) produce one-line inhibition of the production of the conditioned reflex of active avoidance in rats and of their "open-field" motor activity. Both the drugs change the balance of neuroactive amino acids in the animals' brain. However they produce different changes: diazepam increases the content of asparaginic and glutamic acids, while mebicar raises that of gamma-butyric acid. No interrelationship was found between psychotropic and vegetotropic effects of the tranquilizers.

A new original tranquilizer mebicar exerts a protective action on some parameters of body function under the influence of extreme conditions (stress, hypoxia). Antihypoxic effect of the drug manifests within a wide dosage range (100-1000 mg/kg) and compares favourably with the effect of sodium hydroxybutyrate. Mebicar does not affect the muscle tone, movement coordination or working capacity of the animals. It is suggested that the normalizing action of mebicar as tranquilizer and antihypoxic agent may be related to its involvement in metabolism.

Mebicar therapy resulted in a reduction of the degree of deficient disorders of thinking in 27 of 50 patients with paranoid schizophrenia and normalization of indices of mental working capacity, attention and memory, shortening of the time of visual-motor disjunctive reaction in 50 patients with borderline states. Mebicar was shown to possess a nootropic effect which differs qualitatively from that of piracetam.

The results of the experimental and clinical studies showed that administration of mebikar in combination with neuroleptics reduced the degree of side effects of the neuroleptics without decreasing their antipsychotic effect.

It was shown that the psychotropic agents diazepam (1-2 mg/kg), sodium hydroxybutyrate (50-100 mg/kg) and mebicar (250-500 mg/kg) exert a protective action in experimental arrhythmias. This effect is determined by the ability of the drugs to reduce intoxication phenomena, as well as by their antihypoxic and stress-protective properties. On the other hand, the drugs exert an antiarrhythmic effect proper, interfering with potassium ion balance. The protective effects of diazepam, sodium hydroxybutyrate and mebicar enable their application in combined therapy of arrhythmias of varying genesis.

By its effects mebicar -- a derivative of bicyclic bis-ureas -- may be refered to psychotropic drugs occupying a middle position between tranquilizers and neuroleptics. The drug inhibits the orientation reaction in albino mice, potentiates the action of narcotic hypnotics, abolishes the conditioned reflex reaction of avoidance, displays central adrenolytic activity, interferes with the norepinephrine metabolism in the brain stem and modifies the permeability of the blood-encephalic barrier, like this is done by the known neuroleptics. The substance is little toxic, does not exert any direct spasmolytic action on the isolated organs.

It was shown in experiments on mice that inhibition of the exploratory activity by ftoracizin, phenazepam, scopolamine hydrobromide and their combinations predominates in comparison with muscle relaxation. Phenazepam administered at the low dose (0.025 mg/kg) by its depressive effect on the central nervous system was an antagonist of ftoracizin and a synergist of scopolamine. Ftoracizin and scopolamine show a mutual dose-effects-dependent antagonism in the inhibitory action and acute toxicity (LD50).

Use was made of a model system initiating lipid peroxidation, that contained phosphate buffer, H2O2 and eosine. Chemiluminescence of the system decreased after addition to rat brain synaptosomes, thereby indicating the presence of antioxidants in the animals' brain. After addition of brain synaptosomes of rats poisoned with high lethal doses of armine (0.4--0.5 mg/kg) a prooxidant effect was observed. It was manifested in the elimination of the effect of natural antioxidants contained by synaptosomes of normal rats. Addition of acetylcholine, armine, DFP and oxazyl at concentrations of 1.10(-4) 1.10(-3) M to the model system containing rat brain synaptosomes entailed a considerable intensification of chemiluminescence. Atropine and scopolamine did not produce any substantial effect on chemiluminescence, whereas dipiroxim exerted an overt antioxidant effect. The conclusion is made about the possibility of activating the system of lipid peroxidation as one of the components of the toxic action of anticholinesterase agents.