[Changes in the sleep-wakefulness cycle in experimental Parkinson's syndrome]. / Izmeneniia tsikla bodrstvovanie-son pri éksperimental'nom parkinsonicheskom sindrome.

It was demonstrated in rat experiments that in modelling the akinetico-rigid parkinsonian syndrome by injecting kainic acid into the caudate nuclei the phases of wakefulness and light slow-wave sleep decreased while the phase of deep slow-wave sleep increased. In the tremorogenic from of the parkinsonian syndrome induced by reserpine the phases of wakefulness and deep slow-wave sleep decreased in the rats while the phases of light slow-wave and paradoxical sleep increased. In destruction of the substantia nigra with kainic acid the phase of paradoxical sleep reduced. The results of the study are discussed from the standpoint of the generator mechanisms of the development of neuropathological syndromes and the mechanisms of the interrelations of parkinsonism and epilepsy.

[Effects of extracts of different parts of the brain of kindled animals on seizure activity of recipient rats]. / Vliianie ékstraktov razlichnykh otdelov mozga kindlingovykh zhivotnykhna sudorozhnuiu aktivnost' krys-retsipientov.

The peptide-containing fraction was emitted from the hippocampal and ventral mesencephalic region tissue of rats kindled with subconvulsant doses of corazol. Extracts were prepared by the help of hot acetic acid on the stage of generalized clonic-tonic seizure development. The intraventricular injection of VMR-extracts in relatively high dose increased seizure reactions which were induced in intact recipient rats by intraperitoneal corazol injection. The intraventricular injection of the extract in relatively low dose (100 times less) suppressed corazol-induced seizures in recipients. Data are discussed from the point of view of pathological epileptic system formation and the role played by peptides in supporting it's activity during pharmacological kindling.

[Effect of the destruction and activation of the caudate nuclei on the convulsive action of corazol kindling]. / Vliianie razrusheniia i aktivatsii khvostatykh iader na sudorozhnye éffekty korazolovogo kindlinga.

Chronic experiments on the rats have shown that the pharmacological destruction of caudate nuclei significantly elevates the general brain excitation and induces rapid development of the corazol kindling. The hippocampal destruction exerts an opposite effect. Regression analysis of this processes has shown that mechanism of the general brain excitation and those of epileptogenesis are different on the stage of the developing kindling. Caudate nucleus activation induces powerful inhibition of kindling behavioral convulsive reactions and its electrographic epileptic activity. These data suggest that the caudate nucleus is a significant structure of the antiepileptic brain system and confirm G. N. Kryzhanovsky's concept about the system-antisystem interrelationship in case of neuropathologic syndromes as a result of the system hyperactivity.

[The role of the substantia nigra in the anticonvulsive and antiaggressive effects of diazepam during pharmacological kindling]. / Rol' chernoi substantsii v protivosudorozhnykh i antiagressivnykh éffektakh diazepama pri farmakologicheskom kindlinge.

The seizure activity was investigated on the model of pharmacological kindling which was induced by repeated picrotoxin injections in the subthreshold dose, after the tryptic fragment of T5 protein-human diazepam binding inhibitor (DBI) (10 micrograms) injection into a reticular part of substantia nigra. An increase in the seizure reaction and suppression of the antiseizure diazepam action were observed. Intranigral DBI injection induced no change in a threshold of "attacks" in rats which were induced through electric shocks delivered to animals with an electrode floor and no changes in antiaggressive diazepam action were observed under such conditions.

[Development of motor and emotional disorders in rats during daily administration of subliminal doses of picrotoxin]. / Formirovanie dvigatel'nykh i émotsional'nykh rasstroistv u krys pri ezhednevnom vvedenii pikrotoksina v podporogovi doze.

It was shown in the experiments on rats, that three neuropathological syndromes develop as a result of daily subthreshold picrotoxin injections (1.25 mg/kg). Maximal expression of syndromes was different during various periods of kindling. The development of seizure syndrome was followed by prevalence of enhanced electrical activity in hippocampus; the development of "akinetic" syndrome was the same in the caudate nuclei. Data are discussed on the positions of theory of the generator, determinant and systemic mechanisms of neuropathological syndromes.

[Metabolic characteristics of the myocardium and muscle tissue of the thigh in rats]. / Metabolicheskie osobennosti myshechnoi tkani serdtsa i bedra u krys.

Myocardium and skeletal muscle of white rats have a number of specific features in metabolism of carbohydrates. The skeletal muscle is characterized by high intensity of glycolytic processes and glycolytic substrate phosphorylation, that is testified to by the activity of the terminal glycolysis stage enzymes (pyruvate kinase, lactate dehydrogenase, its isoenzyme spectrum) and by the content of lactate and pyruvate metabolites. In contrast to skeletal muscles, the activity of NAD-dependent malate dehydrogenase in the myocardium is significant both in cytoplasm and in mitochondria. This activity corresponds to a high level of malate and oxaloacetate metabolites and to the activity of NADP-dependent malate dehydrogenase, playing a connective role between glycolysis, the cycle of tricarboxylic acids and glyconeogenesis. Phosphoenolpyruvate carboxykinase, catalyzing the transformation of cytoplasmatic oxaloacetate into phosphoenolpyruvate is more active in the skeletal muscles where the intensity of the tricarboxylic acids cycle reactions is lower and the activity of glycolysis is higher than that of myocardium.

[Effect of delta sleep-inducing peptide, anticonvulsant preparations and nicotinamide on generalized seizure activity]. / Vliianie del'ta-sonindutsiruiushchego peptida, protivosudorozhnykh preparatov i nikotinamida na generalizovannuiu sudorozhnuiu aktivnost'.

The influence of delta-sleep inducing peptide (DSIP) upon seizures induced by corazol, bicuculline, picrotoxin, strychnine, thiosemicarbazide were investigated in experiments on F1(CBA X C57 BL/6) mice. It was shown that DSIP increased the latency of first seizure manifestation which were induced by corazol, bicuculline and picrotoxin and also resulted in a suppression of seizure severity of corazol and bicuculline induced seizures. Anticonvulsant action of DSIP was evident under the condition of the mild severity seizures development. The effect of DSIP was mostly pronounced in range of its doses from 10 to 100 mcg/kg. DSIP when combined with phenobarbital, carbamazepine, diphenylhydantoin or nicotinamide enhanced the antiepileptic effects of these anticonvulsant drugs.

[The effect of delta sleep-inducing peptide on the convulsive activity in corasol kindling]. / Vliianie peptida del'ta sna na sudorozhnuiu aktivnost' pri korazolovom kindlinge.

The influence of intraperitoneal delta-sleep inducing peptide (DSIP) injection (100 micrograms/kg) on the epileptic activity was investigated in the experiments on Wistar rats and (CBA X C57B1/6)F1 mice. The model of chronically developing epileptic activity--the model of pharmacological kindling--was created by daily repeated corasole injections in subconvulsive doses (30 mg/kg). It has been shown that DSIP injection delayed the manifestation of generalized seizures during kindling, led to the suppression of seizure activity and reduced the mortality rate of animals that developed kindled seizures. The antiepileptic effect of DSIP was observed throughout the period of 5 minutes to 24 hours after the injection. Naloxone (2.5 mg/kg) did not change the antiepileptic effect of DSIP.

[Modelling of the parkinsonian syndrome by the administration of kainic acid into the caudate nucleus]. / Modelirovanie parkinsonicheskogo sindroma putem vvedeniia kainovoi kisloty v khvostatye iadra mozga.

The experiments on rats have shown that bilateral administration of kainic acid (0.1-0.15 microgram) into the rostral parts of caudate nuclei led to the development of hypokinesia and rigidity. An increase in the electrical activity--the formation of the generator of pathologically increased excitement (GPIE) was noted in a zone of kainic acid injection. Rigidity and hypokinesia were attenuated and the GPIE activity was depressed after cyclodol (1-10 mg/kg) or L-DOPA (100-200 mg/kg) administration. Combined administration of cyclodol (2 mg/kg) and L-DOPA (50 mg/kg) induced potentiated antiparkinsonian effect. Dopamine microinjections into the GPIE area depressed its activity and abolished rigidity and hypokinesia. These data suggest that the Parkinson syndrome develops under the influence of GPIE induced by kainic acid administration into caudate nuclei.

[Changes in the dehydrogenase and GABA transaminase activity in the cerebral cortex during corazol kindling]. / Dinamika aktivnosti nekotorykh degidrogenaz i transaminazy GAMK v kore bol'shogo mozga pri korazolovom kindlinge.

The experiments on (CBA X C57BL/6)F1 mice have shown that regular corazol injections in subliminal doses stimulated seizure susceptibility (pharmacological kindling). Cytophotometric assay of the activity of oxidative metabolism enzymes (glutamate dehydrogenase, malate dehydrogenase, succinate dehydrogenase, alpha-oxoglutarate dehydrogenase, lactate dehydrogenase) and GABA-transaminase in the sensorimotor cortex of kindled mice in post-convulsive period, and 24 hours or 30 days after corazol injections were discontinued, has revealed some specific alterations of the enzymes under study, that suggest the existence of two phases of energy metabolism disturbances. The first phase (24 hours after corazol injections were discontinued) is characterized by intensified succinic acid oxidation, while the second phase (30 days after the last injection) is characterized by anaerobic glycolysis in neuronal and glial cells. Inhibition of GABA-transaminase activity was particularly marked in postconvulsive period. From a molecular point of view these data may be considered as enzyme disturbances during stimulation of seizure susceptability or seizure activity and as a compensation component ensuring anticonvulsive mechanisms and reparative processes (antagonistic principle of molecular mechanism regulation) during activation of antiepileptic system.

[Effect of destruction of the hippocampus and caudate nucleus on the development of epileptic activity during corazole kindling]. / Vliianie razrusheniia gippokampa i khvostatogo iadra na razvitie épilepticheskoi aktivnosti pri korazolovom kindlinge.

Experiments were carried out on random-bred white rats (250-350 g). Kindling was induced by daily intraperitoneal corazol injections in subthreshold (subconvulsive) doses (30 mg/kg). It has been demonstrated that bilateral hippocampal destruction did not change the seizure threshold, while bilateral caudate nucleus destruction lowered it. Hippocampal destruction delayed corazol kindling development and also accelerated the lowering of seizure susceptibility after corazol injections were discontinued, as compared to control animals. Caudate nucleus destruction induced more marked seizure reactions in the first 14 days after corazol injections were started. There were no significant differences in seizure manifestation severity in kindled and control groups. These data point to an essential role of caudate nucleus as an element of antiepileptic system and support the concept that hippocampus plays a role of pathologic determinant which is associated with the formation of an epileptic system underlying corazol kindling.

[The hippocampus as the determinant structure generating epileptic activity during korazol kindling]. / Gippokamp kak determinantnaia struktura, generiruiushchaia épilepticheskuiu aktivnost' pri korazolovom kindlinge.

It has been shown in chronic experiments on rats that two periods of EEG and behavioral alterations may be distinguished during korazol kindling. The bursts of slow waves and spike-wave activity appear on the EEG during the first period as response to subthreshold doses of korazol, which is accompanied behaviorally by standing and myoclonuses. The second period is characterized by the appearance of high-frequency polymorphous generalized seizure discharges on the EEG accompanied by clonicotonic seizures. Interictal and ictal epileptic discharges appear primarily in the hippocamp and then in other brain structures during the development of korazol kindling. The conclusion is made that the hippocamp plays the role of a pathological determinant structure in the development of chronic brain epileptization during korazol kindling.

[Effect of electric stimulation of the dentate nucleus of the cerebellum on epileptogenic foci in the cerebral cortex]. / Vliianie élektricheskoi stimuliatsii zubchatogo iadra mozzhechka na épilepticheskie ochagi v kore golovnogo mozga.

It has been shown in acute experiments on cats that electrical stimulation (ES, 100-300 Hz) of the dentate nucleus leads to suppression of interictal discharges elicited by application of low concentrated penicillin solution to the neocortex. ES of the nucleus causes activation of discharges in a more powerful focus of seizures. As its activity gradually attenuates the seizure discharges are suppressed during ES. The period of focus existence is shortened by ES of the nucleus. ES of the ipsilateral nucleus produces no marked effect, leading only to the decreased frequency of seizure discharges. It is concluded that the dentate nucleus plays a significant role as part of the brain antiepileptic system.

[Changes in the spectrum of LDH isoenzymes in foci of epileptic activity induced by penicillin in the cerebral cortex of rats]. / Izmeneiia spektra izofermentov LDG v ochagakh épilepticheskoi aktivnosti, vyzvannykh penitsillinom v kore golovnogo mozga krys.

The correlation between electrophysiological changes and isozymes of LDH of the rat brain cortex was studied in seizure foci induced by application of sodium penicillin. It was discovered that activity of LDH1 was suppressed, and that of LDH5 fraction was elevated in the determinant focus, which indicates the enhanced glucose anaerobic transformation. The spectrum of LDH isozymes did not practically differ from the indicators in control animals in a homotopic region of the contralateral hemisphere prior to creation of the mirror focus. The anaerobic processes were found to be increased in the mirror focus and in the determinant one as well. Similar pattern of changes in electrophysiological and neurochemical characteristics in the determinant and dependent mirror foci attests to the formation of a pathological system out of the two epileptic foci.

[Effect of determinant on formation of the complexes of hyperactivity foci in rabbit cerebral cortex]. / Obrazovanie kompleksov ochagov giperaktivnosti v kore mozga u krolikov pod vliianiem determinanty.

With the use of weak strychnine solutions foci of enhanced excitability working in independent modes were created in the brain cortex of rabbits during acute experiments. The hyperactive excitability focus induced by concentrated solutions of strychnine played the role of a determinant structure. It enhanced the activity of other foci, united them into a single functional complex and determined the activity pattern of the entire complex. This complex of foci could be destroyed by depression of the determinant focus activity. Disconnection of any other (dependent) focus failed to destroy the complex. The results derived during the research on the new model confirm the general concept of the role played by the determinant structures in the activity of the central nervous system.

[Interaction of excitatory foci and their complexes in the cerebral cortex]. / Vzaimodeistviia ochagov vozbuzhdeniia i ikh kompleksov v kore bol'shikh polusharii.

Relations between excitation foci and their complexes in the cerebral cortex were studied in acute experiments on cats. Excitatory foci were produced by application of solutions of strychnine, penicillin and acetylcholine with prozerine in different concentrations. Two main types of interrelations were established: the determinant and the dominant ones. It was shown that a powerful excitation focus may enhance and synchronize the activity in weaker foci, integrate them in a single functional complex and determine the pattern of its activity (determinant relationships). It may also suppress the activity of previously created foci (dominant relations). The latter form of interrelations was observed either in the transitional stage during formation of the complex or it had an independent meaning. Such types of functional interrelations were observed both between separate foci and their complexes.

[Effect of stimulation of the paleocerebellar cortex on the multifocal cortical epileptogenic complex]. / Vliianie stimuliatsii paleotserebelliarnoi kory na mnogoochagovyi korkovyi épilepticheskii kompleks.

Effects of paleocortex electrical stimulation on multifocal epileptic complex of the brain cortex alone and in combination with benzodiazepines (diazepam, phenazepam) were investigated in experiments on cats. The animals developed complex reactions which included the increased frequency of seizure potentials during stimulation, their suppression after the cessation of stimulation and the postsuppression rise of frequency (dyssuppression). This points to the dualistic character of cerebellar effects on the brain cortex. On being administered before stimulation benzo-diazepines significantly changed the above effects: activation and dyssuppression first disappeared, whereas the suppression of the epileptic activity in the brain cortex remained unchanged.

[Effect of electric stimulation of the caudal reticular nucleus of the pons on foci of epileptic activity in the cerebral cortex]. / Vliianie élektrostimuliatsii kaudal'nogo retikuliarnogo iadra mosta na ochagi épilepticheskoi aktivnosti v kore golovnogo mozga.

It was shown in experiments on cats that electrostimulation (ES) of the nucleus caudalis reticularis pontis under the destruction of the central grey matter suppressed discharges in a single epileptic focus, created with application of strychnine to the brain cortex and did not suppress the epileptic activity in the complex of foci, formed under the influence of a determinant focus after local application of strychnine to different zones of the neocortex. After increasing the number of foci in the complex the resistance of the latter to suppressive effects of ES of the nucleus caudalis increases too. The complex reduction owing to liquidation of its foci (local application of nembutal) facilitates the suppressive effects of ES of the nucleus caudalis. Under prolonged inhibition of the epileptic activity in the focus, the coagulation of the nucleus caudalis leads after its long-term ES to the recovery of the epileptic activity. The evidence obtained is discussed from the standpoint of the properties of the pathological system (epileptic complex) and the role of the "antisystem" in suppression of its activity.