Calcium-dependent phospholipid binding proteins associated with the membranes of rabbit skeletal muscle.

By using extraction in the presence of Ca2+ and Triton X-100 and then in the presence of EGTA without detergent, a set of Ca2+-dependent phospholipid binding proteins has been identified in the membranes of transverse tubules (T-tubules) and sarcoplasmic reticulum (SR), isolated from rabbit skeletal muscles. Longitudinal SR, junctional SR and T-tubule membranes yielded about 9, 14 and 3.3 micrograms of EGTA-soluble proteins per 1 mg of membrane protein, respectively. In the presence of 1 mM CaCl2, 68 and 33 kDa proteins of T-tubules and junctional SR as well as 30 kDa protein of T-tubules were shown to bind to liposomes made of 1:1 w/w mixtures of (i) phosphatidylcholine and (ii) phosphatidylserine, phosphatidic acid, or phosphatidyl ethanolamine. In the presence of EGTA, the above-mentioned proteins were mostly found in the supernatants. Binding of the proteins with liposomes consisting of pure phosphatidylcholine was negligible.

Influence of the inhibition of free-radical oxidation processes in early postnatal ontogenesis on learning in adult rats.

The influence of the neonatal administration of the synthetic antioxidant mexidol on teaching rats an active avoidance conditioned reflex at the age of two months was studied. It was established that the inhibition of free-radical oxidation in the tissues of three to seven day old infant rats subsequently leads to facilitation of the learning process: to a decrease in the latent period of the avoidance reaction by a factor of 4-6, a two-fold increase in the conditioned reflex response, and a decrease in total motoric activity at the stage of the stably developed reaction.

[Age-related features of dynamics of the bioelectric characteristics of command neurons in edible snail]. / Vozrastnye osobennosti dinamiki bioélektricheskikh kharakteristik komandnykh neironov vinogradnoi ulitki.

Differences in changes of the AP amplitude ratios induced with depolarizing current in respect to the AP in spontaneous unit activity, were found between two age groups of mollusks.

[The effect of the inhibition of free-radical oxidation processes in early postnatal ontogeny on learning in adult rats]. / Vliianie ingibirovaniia protsessov svobodnoradikal'nogo okisleniia v rannem postnatal'nom ontogeneze na obuchenie vzroslykh krys.

The effect on neonatal administration of synthetic antioxidant mexidol on avoidance conditioning was studied in 2-month old rats. The inhibition of the free-radical oxidation in the tissues of 3-7-day old rats considerably facilitated subsequent process of learning: the avoidance response latency was reduced by 4-6 times, the conditioned response was two-fold augmented, and total motor activity was reduced at the stage of a stable response.

[Dynamic aspects of RNA metabolism in the brain of mollusca during electrical effects]. / Dinamicheskie aspekty obmena RNK v gangliiakh molliuskov pri elektricheskikh vozdeistviiakh

The dynamics of RNA and protein metabolism (as indicated by the incorporation of labeled precursors) during electrophysiological 'learning" and electrical stimulation of isolated ganglia of the snails Tritonia diomedia and Helix pomatia has been investigated. 'Learning" phenomenon manifested itself in the maintenance of synchronous discharges in the electrical activity of the neurons after cessation of the stimulus. At all the electrical stimulations, fast periodic processes of accumulation-degradation of RNA and protein were observed. Radioautographic studies indicate that these processes begin at first in the glia and then in the neurons. The pattern of incorporation of the precursor into the protein is similar to that into RNA, indicating that short-living RNA is involved into the synthesis of short-living proteins. Aurantin (a mixture of actinomycines) inhibits glial synthesis of RNA to a greater extent than neuronal one,-both at rest and electrical stimulation. On the other side, aurantin hinders or even completely blocks "learning" phenomenon. It is suggested that normal RNA metabolism is necessary for the formation of trace phenomena. No essential differences in the metabolism of RNA, protein and nucleotides were found during "learning" and stimulation.

[Retardation of growth and development of rats induced by inhibition of protein synthesis at early postnatal ontogenesis]. / Zaderzhka rosta i razvitiia funktsii krys v rannem vozraste pri ugnetenii belok-sinteziruiushchei sistemy

Treatment of rats with aurantine for 7-30 days reduces the growth and development of animals, and especially of skeletal muscles. Low relative weight of muscles in aurantine-treated animals was accompanied by low resting and action membrane potentials. Incorporation of labelled uridine and lysine into muscles, heart, brain and liver was decreased. Retardation in the growth and development of skeletal muscles resulted into unfavourable shift of the ratio body weight/surface and led to prevalence of catabolic processes over anabolic ones (increased oxygen consumption, heart and respiration rate in experimental animals). These changes are probably related not only to the inhibition of protein synthesis, but to disturbance of regulatory mechanisms, which reveals itself in an increased norepinephrine content of the brain stem and in the increased cholinesterase activity in cardiac pacemaker.

[The mechanisms of the reorganization of functional systems in the ontogeny of rats]. / Mekhanizmy reorganizatsii funktsional'nykh sistem v ontogeneze u krys.

Functional systems as well as other mechanisms of regulation of animal behavior (reflexes) have very high adaptive properties. Specific mechanisms of reorganization of the functional systems have been elaborated during ontogenesis to adapt an individual to changing environment.

[The intercellular connection of axons-capillaries in the light of genetically determined resistance to emotional stress]. / Mezhkletochnaia sviaz' akson-kapilliar v svete geneticheski determinirovannoi ustoichivosti k émotsional'nomu stressu.

Genetic factor is one of the main factors of systemic organization of animal resistance to emotional stress. This notion served as a basis for comparing ultrastructural specific of connections between nervous and vascular systems in catecholamine-synthesizing areas of different lines of Wistar and August rats. Quantitative difference has been observed in the structure of cell junctions. This difference may determine different level of adaptive reactions of animals to stress.