Changes in the levels of inhibitory and excitatory amino acids in the brain structures of female rats with cobalt epileptogenic focus during different phases of the estrous cycle.

We studied changes in the levels of inhibitory and excitatory neurotransmitters in female rat brain structures during different phases of the estrous cycle in health and after creation of a cobalt epileptogenic focus at stage I of epileptogenic system development. The most pronounced shifts were found in the contralateral cortex, where the levels of GABA and glycine decreased significantly during the diestrus-2 phase (corresponding to menstruation), which attests to a convulsive threshold decrease during this period.

[The antiparkinson activity of a new adamantane derivative]. / Protivoparkinsonicheskaia aktivnost' novogo proizvodnogo adamantana.

The activity of the new original compound--hydrochloride N-2-(adamantyl) hexamethylenimine (code A-7) synthesized at the Institute of Pharmacology, Russian Academy of Medical Sciences, was studied on models of akinetic-rigid and tremor manifestations of the parkinsonian syndrome. A-7 completely relieves the akinetic-rigid manifestations of the syndrome and surpasses mydantan and L-dopa in antagonism with haloperidol and triftazine. Just as L-dopa, cyclodol, and mydantan, A-7 alleviates reserpine-induced oligokinesis and restores body temperature which is lowered by reserpine. A-7 possesses evident antitremor activity which advantageously distinguishes it from mydantan which failed to demonstrate antagonism with arecoline. A-7 is promising for further study as a potential agent for the treatment of parkinsonism.

[Sodium oxybutyrate normalizes the central nervous system functions in the progeny of rats subjected to hypobaric hypoxia during pregnancy]. / Natriia oksibutirat mormalizuet funktsii tsentral'noi nervnoi sistemy u potomstva krys, podvergshikhsia gipobaricheskoi gipoksii vo vremia beremennosti.

Two-hour hypobaric hypoxia of rats on day 15 of their pregnancy led to a reduction in weight gain of pups within 20 days after birth, disturbed memory in active and passive paradigms, changed adaptive behavior in the extrapolatory water avoidance test, and impaired sleep in adult animals. Postnatal treatment with sodium hydroxybutyrate given in a dose of 50 mg/kg/day on days 8 to 20 of life normalized mnestic functions of the brain, the process of falling asleep, and physical development which had been impaired by intrauterine hypoxia.

[Effects of melatonin and epiphysectomy on electrical activity of the rat brain at different times of the day]. / Vliianie melatonina i épifizéktomii na élektricheskuiu aktivnost' mozga krys v razlichnoe vremia sutok.

The pineal hormone melatonin in a dose-effect manner (0.1, 1 and 10 mg/kg) reorganized EEG spectral characteristics of rat sensorimotor cortex and hippocampus, decreasing medium (6-12 Hz) and high frequency (12-22 Hz) waves only in the evening. On the contrary, pinealectomy increased high-frequency waves only during morning hours. It is suggested that the observed changes may accompany anxiolytic and hypnotic effects of melatonin.

[An electrophysiological analysis of the action of an antioxidant of the 3-hydroxypyridine class on the cerebral epileptic activity in rats with a cobalt-induced focus]. / Elektrofiziologicheskii analiz deistviia antioksidanta iz klassa 3-oksipiridina na épilepticheskuiu aktivnost' mozga krys s kobal'tovym ochagom.

In experiments on albino male rats with chronically implanted electrodes and an epileptogenic focus in the cortical sensomotor region it was shown that a derivative of 3-hydroxy-pyridine (2-ethyl-6-methyl-3-hydroxypyridine) possesses the pronounced antiepileptic effect. The effect of the agent is related to the functional state of the epileptic system whose resistance to pharmacotherapy depends on the power of the determinant focus.

[Electrographic correlates of the antiamnestic action of nootropic agents following deprivation of the paradoxical sleep phase]. / Elektrograficheskie korreliaty antiamnesticheskogo deistviia nootropov posle deprivatsii paradoksal'noi fazy sna.

During experiments conducted on albino rats the deficiency of passive avoidance retention was shown to correlate not only with the reduction in REM sleep and SWS, but also with disappearance of phasic component of theta-rhythm. Drugs with nootropic mode of action (cleregyl, centrophenoxin, antioxidant 3-xypyridine) recovered the deficiency of passive avoidance retention and increased phasic component of theta-Rhythm, while phenazepam enhanced tonic component of theta-rhythm, and failed to act upon learning deficits. It seems likely from these results that the electrophysiological correlates of antiamnestic effect is the maintenance of proper two-component theta-rhythm and the increase in its phasic component, whereas the destructuring of sleep, including REM sleep reduction is not considered to be key determinant in the action upon memory and learning procedure.

[Pharmacological characteristics of a new phenyl analog of piracetam--4-phenylpiracetam]. / Farmakologicheskaia kharakteristika novogo fenil'nogo analoga piratsetama--4-fenilpiratsetama.

The central neurotropic effects of 4-phenylpyracetam, a new phenyl analog of pyracetam, were studied and compared with the effects of pyracetam, morpholene and 4-phenylpyrrolidone. 4-Phenylpyracetam was found to activate the operant behavior more powerfully, to remove psychodepressant effects of diazepam, to inhibit post-rotational nystagmus, and to prevent the development of retrograde amnesia. Unlike pyracetam, 4-phenylpyracetam exhibits a specific anticonvulsant action. When given in high doses, the compound under study produces psychodepressant effects.

[Characteristics of the anticonvulsant effects of fenazepam]. / Kharakteristika protivosudorozhnykh éffektov fenazepama.

Studies of the new benzodiazepine drug phenazepam comparatively to diazepam, clonazepam, nitrazepam, phenobarbital and diphenylhydantoin have shown that by its anticonvulsant effects phenazepam is similar to clonazepam and differs from other antiepileptic agents. Phenazepam exhibits a pronounced capacity for removing paroxysmal epileptiform discharges induced by cobalt application to the surface of the brain cortex. Prolonged administration induces tolerance to phenazepam as shown by antagonism to strychnine and by capacity for preventing convulsions in maximal electric shock.