The integrity of the social hierarchy in mice following administration of psychotropic drugs.

1 Mice in small groups develop a despotic type of social hierarchy, a feature of which is to resist alteration through the medium of psychotropic drugs. This makes a rapid pharmacologically induced change in the social hierarchy impossible. 2 Patrolling the territory and a certain level of social interaction are both critical factors in maintaining the phenomenon of inertia in the social hierarchy. Psychotropic drugs (diazepam, droperidol and mescaline) altered both these factors to a varying degree and also displayed a differing ability to maintain the inertia of the social hierarchy. 3 A drug-induced alteration in the level of aggression in a subordinate mouse in a group of three does not cause an alteration in its social position. 4 Chronic administration of diazepam, droperidol or mescaline, all of which alter the level of aggression in different ways, can result in an inversion of the social hierarchy where a competitive rival is present in the group of mice. The rate of inversion of the social hierarchy depends on the type of pre-existing social hierarchy. 5 It is suggested that the ability of psychotropic drugs to maintain the inertia of the hierarchy be used as an index of their effect upon certain types of species-specific behaviour; in particular aggression.

Pharmaco-ethological analysis of social behaviour of isolated mice.

The ethological profile of some neuropharmacological substances affecting catecholamines, serotonin and GABA was investigated in isolated mice. Changes in brain noradrenergic, dopaminergic or serotonergic systems, in addition to a block of the inhibitory GABA system, caused "irrepressible" aggression and a lack of sociability in isolated mice. GABA analogues (phenibut, phenylpyrrolidon) and GABA agonists reduce aggression and increase intraspecies sociability; small doses of GABA antagonists (picrotoxin, bicuculline) exert the opposite effect. GABA may play a key part in the control of aggression and sociability in isolated animals. Selective activation of intraspecies sociability with a concurrent reduction of species-specific aggression requires complex pharmacological action.

Pharmaco-ethological analysis of antidepressant drug effects.

An ethological approach to the analysis of antidepressant drug action focuses on the restorative effects of these drugs on intraspecies behavior and locomotor activity. The present analysis reveals that iprazid and amphetamine differentially alter locomotion and intraspecies behavior in mice that were pretreated with reserpine. Fluoxetine restores intraspecies behavior, specifically by increasing the number of passive contacts, but without activating locomotion. Trazodon, pyrazidol and clomipramine restore aggression by dominant mice that was suppressed by aversive stimulation. The restoration of intraspecies behavior among laboratory rodents subjected either to reserpine treatment or to prolonged aversive stimulation may reveal the antidepressant effects of drugs.

Intraspecies behavior of animals based on a model of experimental brain ischemia.

The features of the intraspecies behavior of rats after ligation of the right, left, or both common carotid arteries were studied. It was shown that certain characteristics of behavior change differently following ligation of the right or left common carotid artery. The approach used may be utilized for the assessment of the severity of ischemic brain damage.

[Relationship between the sequelae of zoosocial isolation and individual characteristics of the animal]. / Posledstviia zoosotsial'noi izoliatsii v zavisimosti ot individual'nykh osobennostei zhivotnogo.

The changes were studied of various psychophysiological characteristics of mice behaviour, arising after prolonged solitary isolation in cages. The qualitative specificity of such changes is non-uniform and depends on the animals' individual characteristics (spontaneously aggressive or nonaggressive after isolation). Two types of the consequences of isolation are singled out: 1) General changes (non-specific) arising in all groups of mice; 2) Special changes (specific), typical of a certain group of animals only. In the group of aggressive mice there is a difference between aggression enhanced by isolation, and that which developed in the course of isolation. The most substantial qualitative changes in behaviour takes place in the latter case. It has been suggested that only individual approach makes it possible to determine exactly the qualitative aspects of social isolation consequences.

[Pharmacologic analysis of hierarchical relationships in mice]. / Farmakologicheskii analiz ierarkhicheskikh otnoshenii u myshei.

In experiments on mice (put in triads and tetrads) stable domination-subordination relations (DS) of predominantly despotic type were formed. The experiments were staged in specially designed communicating populational cages. Pharmacological evidence of inertness of DS relations in small groups of mice is presented. Critical factors of DS inertness are examined. It is shown that psychotropic drugs of different classes have difficult effect on the maintainance of DS inertness. Prolonged administration of psychotropic drugs suppressing the dominant's aggression may result in DS inversion.

[Group behavior of mice in population cages]. / Gruppovoe povedenie myshei v kommunikatsionnom apparate.

A model of a population cage has been proposed, intended for a quantitative and qualitative estimation of the group behaviour of mice, for determining the type of their interrelations and identifying the dominant in the group. In experiments on 120 mice the fundamental types of interaction between mice (peaceful or conflicting) have been singled out in the apparatus, as well as the behaviour phases of each type of interaction. It has been shown that the type and phases of interaction in mice depend on the presence of a dominant in the group, the sex and age composition of the group, the degree of adaptation to one another, and the previous experience (being kept in isolation or in a group). The final effect of group interaction is determined not by a simple sum of individual characteristics of the animals, but is subordinated to the rules of zoosocial behaviour, i. e. the formation of stage by stage dominant- subordinate relationships.

[Effect of electroshock on intraspecific behavior of mice maintained in isolation]. / Vliianie élektroshoka na vnutrividovoe povedenie myshei, soderzhavshikhsia v izoliatsii.

By means of probabilistic-ethological analysis it was shown on isolated mice that the direct effect of primary electroshock is manifested in an inversion of the isolant's aggressive behaviour into a defensive one. Delayed (24 hours) and chronic effects of the electroshock (applied daily during a week) were manifested in a change of behaviour pattern of the isolants (appearance of the previously absent phase of investigating the partner and the environment before aggressive attack), in diminished probability of appearance of aggression and increased intraspecies sociability. All effects of the electroshock on intraspecies behaviour had rigid temporal limitations.

[New model for studying group learning in mice (synthesis of conditioned reflex and ethologic approaches]. / Novaia model' dlia izucheniia gruppovogo obucheniia u myshei (sintez uslovnoreflektornogo i étologicheskogo podkhodov).

In experiments on mice it has been shown that synthesis of conditioned reflex and behavioural approaches is advantageous for the more complete qualitative and quantitative characteristic of group learning and performance of conditioned avoidance reaction in rodents. The efficiency of group learning and performance of this reaction depend not only on the individual characteristics of animals (ability or inability to learning) but also on the type of hierarchic relationships in the group. The possibility is suggested to use this model for investigating the modulating effect of psychotropic agents on group learning and performance of avoidance reaction.

[Relation between reactions to pain and the hierarchical rank of animals]. / Zavisimost' reaktsii na bol' ot ierarkhicheskogo ranga zhivotnykh.

Intraspecies experience of domination or subordination in mice is an important factor predetermining their specific behaviour in response to painful stimuli, The significance is emphasized of ethological investigations for studying behavioural reactivity to pain and correct differentiation of responses of "defence-subordination" and "aggression-offence" types. The specificity of diazepam effect on the character of behaviour in response to pain was analysed in animals of different hierarchic rank.

[Probabilities and ethologic analysis of the zoosocial behavior of grouped and isolated mice]. / Veroiatnostnyi i étologicheskii analiz zoosotsial'nogo povedeniia sgruppirovannykh i izolirovannykh myshei.

The effectiveness of probabilistic and ethological approaches to the analysis of normal and pathological animal behaviour is shown. The probabilistic analysis of the frequency, duration and sequence of a large variety of behavioural acts and postures permits to single out the most significant events and diad transitions in the interaction between two animals (previously isolated or grouped). Computer and probabilistic analysis reveals sharp differences in the structure of these acts and their interdependence in isolated and in grouped mice. It is noted that in isolation there occur fixation of the program of aggressive behaviour, a sharp narrowing of the spectrum of possible transitions from aggression to other forms of intraspecific behaviour, aggression being little controlled by intraspecific inhibitory factors which is regarded as pathology of behaviour.

[Discrete and continuous mathematical models of intraspecific behavior in the pharmacoethology of the mouse]. / Diskretnaia i nepreryvnaia matematicheskie modeli vnutrividovogo povedeniia v farmakoétologii myshei.

An algorithm and software library were compiled in order to interpret the intraspecies agonistic animal behaviour in terms of discrete or continuous mathematical model. Applied aspects of the use of mathematical models in pharmacoethology were shown on concrete examples. The ways of construction of standard prototypes, and the integrative criteria of psychotropic drugs action were developed. The possibility was shown of identification of unknown substances by comparing with standard drugs by calculating the norm of standardized matrices.

[A computer ethological-pharmacological analysis of the intraspecific behavior of primates]. / Komp'iuternyi étologo-farmakologicheskii analiz vnutrividnogo povedeniia primatov.

Experiments were performed on primates (Cercopithecus sabeus, Macaca maurus, Cebus apella). Possibility to formalize the structure of normal and pathological monkey behaviour was shown by computerized technique. Rigid dominant-subordinate structures (linear type) were demonstrated on Macaca maurus, Cercopithecus sabeus, Cebus apella. These structures display some variants of normal relationship between monkeys. Raising in isolation from conspecifics determines behavioural disadaptation and pathological behaviour, e.g. "timid-defensive" syndrome. Model of "timid-defensive" syndrome in isolated primates seems to be useful for psycho-pharmacological research, for assessment of anxiolytic and antidepressive properties of drugs.

[Effect of unilateral spreading cortical depression on intraspecies aggression and sociability of isolated mice]. / Vliianie odnostoronnei korkovoi rasprostraniaiushcheisia depressii na vnutrividovuiu agressiiu i obshchitel'nost' izolirovannykh myshei.

It has been shown that aggressive forms of behaviour are controlled preferentially by the left hemisphere and sociability by the right one. Consequently, the opposite poles of the continuum "aggression-sociability" have different lateralization. Interconnection between functional interhemispheric asymmetry and aggression degree has been revealed: in high-aggressive mice the differences in the effect of left and right hemispheres inactivation are expressed stronger as compared to low-aggressive and nonaggressive animals.

[Intraspecies animal behavior in a model of experimental cerebral ischemia]. / Vnutrividovoe povedenie zhivotnykh na modeli éksperimental'noi ishemii mozga.

Specifics of intraspecies behaviour following ligation of both or either one of the two carotid arteries, were studied in rats. Certain behavioural features are altered in different ways depending on ligation of the right or left carotid artery. The approach can be applied to evaluation of graveness of the brain ischemic lesion.