[Neuroactive complexed zinc compounds from bovine brain]. / Neiroaktivnye kompleksnye soedineniia tsinka iz mozga krupnogo rogatogo skota.

The fraction obtained from acidic extract of bovine brain homogenate after several steps of chromatographic purification provokes spontaneous aggressive encounters in rats upon intracerebroventricular injection. The simultaneous long-term raising of electric shock-induced aggression with the suppressing of muricidal and intraspecies aggressive behaviour has been observed. Intravenous and intraperitoneal injections of this fraction induce no behavioural changes in rats. It has been determined that the fraction consists of complex compounds of zinc with various aliphatic amines. A similar or higher behavioural activity has been discovered in series of synthetic complexes of zinc with different ligands, that are suggested for use in modelling any nervous and psychiatric disorders connected with an increased aggression level.

Synthesis of proteins in the critical periods of early postnatal ontogenesis: its role in the formation of intraspecies aggressive behavior of rats.

The significance of the synthesis of the protein in the brain for the formation of intraspecies aggressive behavior of isolated males in early postnatal ontogenesis, under the influence of social contacts, was revealed in experiments on 200 mongrel rats. Chronic administration of cycloheximide (0.5 mg/kg; intraperitoneally), a protein synthesis blocker at the stage of translation, to infant rats from the 15th to the 30th postnatal days, prior to daily three-hour sessions of contacts between them, disrupted the formation of intraspecies aggressive behavior. This was manifested at adult age by their hyperaggressivity and by changes in the proportions of various reactions in the integral act of aggressive behavior.

[Protein synthesis in the critical periods of early postnatal ontogeny: its role in the development of the interspecific aggressive behavior of rats]. / Sintez belka v kriticheskie periody rannego postnatal'nogo ontogeneza: ego rol' v formirovanii vnutrividovogo agressivnogo povedeniia krys.

Chronic administration of cycloheximide to young rats from 15-th to 30-th postnatal day before daily 3-hour seances of their contacts, disturbed the formation of animals intraspecies aggressivity. In adults it was manifested by hyperaggressivity and by changes of proportions of different reactions in the integral act of aggressive behaviour. By their character these disturbances were close to those observed in the young rats completely deprived of social contacts in this period of ontogenesis.

["Sensitive periods" in the systemogenesis of intraspecific aggression in rats]. / "Chuvstvitel'nye periody" v sistemogeneze vnutrividovoi agressii krys.

As a result of experiments conducted on male outbred white rats, approximate limits were established of two sensitive periods for the formation of intraspecies aggression of rats under the influence of contacts with the animals of the same age: sensitive period from 12th to 21st postnatal day for changing from playing behaviour into the aggressive one; and 40-60 days for differentiation of the aggressivity against the males and females. It was shown, that despite considerable change in the spectrum of aggressive reactions of early isolated rats towards intruders and low effect of these reactions, judging by response behaviour of intruders, these reactions were based on the emotionally-motivational state, typical for the formed aggressive behaviour. It was also found, that disturbances of the aggression formation in rats isolated in early age, were caused by deprivation of contacts with rats of the same age and not by general informational impoverishment of the environment where rat pups were bred.

[The formation of predatory aggressiveness in the ontogeny of rats]. / Formirovanie khishchnicheskoi agressivnosti v ontogeneze krys.

In tests on outbred male rats the problem was studied of the existence of "sensitive periods" in the formation of rats predatory aggression. Breeding of small rats together with mice from the first till 60-th postnatal day considerably inhibits their muricidity in the adult age, what is manifest in tests of predatory aggressiveness till the 270-th day of rats life. Breeding of mice together with rats in the age of 1-20, 20-40, 40-60 and 20-60 postnatal days does not influence significantly their muricidity. Antiaggressive effect of breeding of mice with adult rats from the 150-th to the 210-th day is a short-term one, and breeding of mice with old rats in the age of 540-600 postnatal days does not significantly effect the muricidity.

[Effect of various periods of social isolation of juvenile rats on the level of their intraspecies aggression at a sexually mature age]. / Vliianie razlichnykh srokov sotsial'noi izoliatsii iuvenil'nykh krys na uroven' ikh vnutrividovoi agressivnosti v polovozrelom vozraste.

Isolation of male outbred white rats from the same age rats at 12-30 and 15-30 days of postnatal life increases their aggressiveness in pubertal age and causes a change of aggressive reactions spectrum towards the decrease of attacks and increase of threats in relation to intruders. These changes in the ontogenetic formation of rats aggressive behaviour are not compensated by the experience of rats social intercourse in the period 30-70th days. A hypothesis is made about the existence of sensitive period of rats aggressive behaviour formation with the approximate limits 15th-30th days of postnatal life during which under the influence of contacts with rats of the same age prerequisites are created for consolidation of various agonistic reactions in resultant act of mature aggression.

[Can a mouse be the object of maternal aggression on the part of a rat?]. / Mozhet li mysh' byt' ob"ektom materinskoi agressii so storony krysy?

It has been found that mice do not evoke interspecies maternal aggression in lactating female rats even if the latter kill little rats of their litter. Putting mice in cages with rats bearing for the first time, and their progeny for 24 hours after labor, increases the frequency of infanticide and progeny leaving by female rats. The infanticide by lactating rats towards their own litter does not depend on whether these females exhibit muricid or not. Putting mice in cages with rats 3-6 days before bearing for the first time or during 24 hours after labor by repeatedly bearing rats does not influence the frequency of progeny leaving and infanticide reactions of female rats.

[Is pain-induced aggression actually a defensive form of that behavior?]. / Deistvitel'no li agressiia, vyzvannaia bol'iu, iavliaetsia oboronitel'noi formoi dannogo povedeniia?

25-minute testing of aggressive reactions in constant pairs of male rats, elicited by electric shocks shows that electro-pain aggression of rats is not a homogeneous process, but consists of three successive stages: orienting-investigatory activity and attempts to get out of the chamber; defensive aggression; establishing of relations of domination-subordination and attacking aggression. Division in attacking rats and defending themselves, occurs mainly at final stages of testing (15-25 min); in some pairs reactions of attacking aggression are accomplished by the same rats. It is supposed that rats pain aggression is not a purely defensive form of this behaviour, but a modification of intermale aggression caused by specificity of laboratory conditions.

[Predatory aggressiveness of the rat after intraventricular administration of individual brain-specific proteins of the S-100 group and their peptide fragments]. / Khishchnicheskaia agressivnost' krys posle vnutrizheludochkovogo vvedeniia otdel'nykh mozgospetsificheskikh belkov gruppy S-100 i ikh peptidnykh fragmentov.

Intraventricular injections to rats of the basic fraction of the brain specific protein S-100 in a concentration of 3 mg/ml, significantly facilitates the formation of their predatory aggression induced by the alimentary deprivation and social isolation, expressed in mice killing. This effect is not produced by fragments of S-100 molecules obtained as a result of treatment of the basic protein fraction by proteolytic enzymes. Administration of the minor S-100 fraction, albumin and rats summate brain proteins did not influence animals predatory aggression.

[Changes in predatory and intraspecific aggressiveness of the male rat during food deprivation]. / Izmenenie khishchnicheskoi i vnutrividovoi agressivnosti samtsov krys pod vliianiem pishchevoi deprivatsii.

A significant intensification of intraspecies aggression of mice-killing male rats was manifest under the influence of food deprivation, judging by two aggressive reactions of rats-residents towards intruders and by the number of rats performing such reactions. In conditions of free access to food, the mice-killing and not mice-killing rats did not differ by their intraspecies aggression.

[Correlation between genetic and environmental factors in the display of predatory reactions in the rat]. / Sootnoshenie geneticheskikh o sredovykh faktorov v proiavlenii reaktsii khishchnika u krys.

Manifestation of the hunting and mice-killing reactions by non-linear rats-observers did not depend on the presence of rats killing mice. The absence of such dependence was observed in conditions of free access to food, of food deprivation stimulating predatory aggressiveness, and also of learning in the early postnatal period. Acquisition of the habit of eating killed mice by the rats-observers was facilitated in the presence of rats executing this reaction. It is suggested that in manifestation of the aggressive component of predatory behaviour of rats, a greater role is played by inborn mechanisms while environmental factors are more significant for organization of the alimentary mechanism.

[Effect of endogenous oligopeptides and brain-specific proteins on aggressive behavior in the rat]. / Vliianie éndogennykh oligopeptidov i mozgospetsificiheskikh belkov na aggressivnoe povedenie krys.

In experiments on non-bred males of white rats, the effect was studied on their aggressive behaviour of intraventricular injections of brain-specific proteins of S-100 group, gamma-globuline fraction from the serum of rabbits immunized by proteines S-100 (gamma S-100) and non-immunized rabbits (gamma-SNK) as well as of angiotensin, bradikinin and saline. S-100 lowered intermales aggressivity and that connected with pain, and had phasic inhibitory effects on rats emotional reactivity. gamma S-100 increased the aggressivity connected with pain, did not affect the intermales aggressivity and phasically raised (as well as gamma-SNK) the emotional reactivity. gamma-SNK, angiotensin and bradikinin did not change these kinds of aggressivity. None of the administered agents influenced the level of rats predetary aggressivity.

[Changes in pain sensitivity during electric stimulation of emotiogenic zones of the rabbit hypothalamus]. / Izmenenie bolevoi chuvstvitel'nosti pri élektrostimuliatsii émotsiogennykh zon gipotalamusa u krolikov.

Electrical stimulation of 80% of negative and 82% of positive sites of the rabbit hypothalamus increased the latent period of thermal nociceptive stimulus avoidance and diminished the evoked potential amplitude in the parafascicular complex of the thalamus in response to electrical nociceptive stimulation of the skin. The opposite effects were evoked by subthreshold stimulation of the negative rather than positive sites. Electrical stimulation of neutral sites had not effect on the test parameters of pain sensitivity.