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M Krsiak

Publications and source records attributed to M Krsiak.

At least 37 records · Page 2Linked to original sources

Beta--CCE and FG 7142 increase defensiveness during intraspecies encounters in mice.

The effects were ascertained of two partial inverse agonists at benzodiazepine receptors (beta-CCE and FG 7142) on the incidence of timid (defensive-escape), aggressive, sociable and locomotor activities in both timid and aggressive singly-housed male mice, treated with drugs in paired interactions with untreated non-aggressive males. FG 7142 (5 mg/kg) and beta-CCE (8 mg/kg) increased defenses and escapes without producing other behavioral changes in timid mice. FG 7142 (20 mg/kg) and beta-CCE (1-8 mg/kg) moderately increased defenses and alert postures in aggressive mice and this effect was associated with marked reduction of aggressive behavior. FG 7142 (20 and 80 mg/kg) also decreased walking across cage in aggressive mice. It is concluded that beta-CCE and FG 7142 produced behavioral changes which could be interpreted as "anxiogenic".

Aggression↗

Ethopharmacology: a historical perspective.

Ethopharmacology can be defined as the study of behavioral and other effects of drugs through the use of ethological concepts. The study of drug effects on natural action patterns (motor acts and postures listed in ethograms), with respect to natural settings and to behavior as a whole (all identifiable behaviors occurring during the measurement) represents the basic concepts of ethopharmacology. Although pioneers drew attention to the potential of the ethological approach in pharmacology in the early 1960s, the number of publications utilizing this approach has steadily grown only since the mid-1970s. In the 1980s, modern technology, such as videorecorders, microcomputers and software, has been more widely applied in ethopharmacological experiments, greatly facilitating the observation and quantitative analysis of multiple data. Ethopharmacology is not "another" behavioral pharmacology, but an integral part of it. Rather, it represents one of the tools which can be useful (and sometimes even indispensable) in achieving a better understanding of the behavioral effects of drugs. It is to be hoped that it will be used in concert with other approaches in the future.

Animals↗

Differential effects of six structurally related benzodiazepines on some ethological measures of timidity, aggression and locomotion in mice.

The effects were compared of three 2' chlorophenyl-benzodiazepines (triazolam, clonazepam and lorazepam) and three corresponding 2' deschloro-phenyl-derivatives (alprazolam, nitrazepam and oxazepam, respectively) on the incidence of six ethological elements in both timid and aggressive singly-housed male mice, treated with drugs in paired interactions with untreated non-aggressive males. Alprazolam and oxazepam reduced defensive upright postures and escapes at doses which did not reduce rearing and actually increased walking, while their chlorinated counterparts (triazolam and lorazepam, respectively) decreased incidence of defenses and escapes mostly at doses decreasing locomotor acts involving a similar movement (rears and walks, respectively). Alprazolam and oxazepam also reduced attacks at doses not reducing rears, in contrast to triazolam and lorazepam which reduced attacks only at doses suppressing rearing. Nitrazepam stimulated sniffing partners much more than its chlorinated counterpart clonazepam. The 2' deschloro-phenyl-benzodiazepines were more potent in reducing defensive-escape activities than attacks or locomotion. Yet, none of the benzodiazepines tested produced a complete inhibition of timid defensive-escape behavior at non-sedative doses. The present study suggests that 2' deschloro-phenyl-benzodiazepines are less "sedative" with respect to their "anxiolytic" activity.

Aggression↗

Differences among nine 1,4-benzodiazepines: an ethopharmacological evaluation in mice.

The present study explored whether the profiles of action of benzodiazepines on intraspecies conflict behavior in mice are different. The occurrence of seven behavioral elements was observed in aggressive and timid singly-housed male mice treated with drugs in paired interactions with untreated non-aggressive males. At low doses, some benzodiazepines (alprazolam, oxazepam and diazepam) inhibited defenses, escapes, or attacks, but did not reduce other activities (social sniffing, walking, rearing), and actually increased most of them. At comparable doses, other benzodiazepines (flunitrazepam, nitrazepam, clonazepam and chlordiazepoxide) stimulated only social sniffing, but reduced rearing or walking. Further benzodiazepines (triazolam and lorazepam) reduced defenses, escapes and attacks only at doses that suppressed most of the remaining activities as well. Thus, the nine benzodiazepines tested exhibited different profiles of action in the present study. Alprazolam, oxazepam and diazepam appeared least sedative, while triazolam and lorazepam were most sedative.

Aggression↗

Can social and agonistic interactions be used to detect anxiolytic activity of drugs?

Majority of adult male albino random-bred mice housed singly or in small groups show agonistic behavior on interaction with a strange male mouse: some of them are predominantly aggressive ('aggressive' mice) while others show defenses or escapes even though their partners are not aggressive ('timid' mice). The remaining males not exhibiting agonistic behavior ('sociable' mice) show more social investigation then aggressive or timid mice and more locomotion then timid mice. Active defensive-escape behavior ('timidity') and inhibition of social investigation and of locomotion is much stronger in an unfamiliar cage with a strange male than in a home cage or on interaction with a female. Effects of 50 drugs on behavior of aggressive and timid male mice on agonistic interactions with non-aggressive male mice in neutral cages were tested. Most of the drugs possessing anxiolytic activity in man reduced active escapes or defenses at doses lower than those inhibiting attacks or locomotion and increased social investigation while most drugs without anxiolytic activity did not show these effects. Some anxiolytic drugs reduced tail-rattling (an ambivalent activity presumably reflecting both attack and escape tendency) at doses lower than those reducing attacks and increased locomotion. Only some benzodiazepines (nitrazepam, oxazepam and diazepam) produced the whole spectrum of these effects indicating a reduced defensive-escape tendency. The present results suggest that a selective inhibition of defensive-escape tendency on agonistic interactions can be a good predictor of anxiolytic activity of drugs. Profiles of effects of seven benzodiazepines in the present model of agonistic interaction to some extent differed: triazolam, clonazepam and flunitrazepam were more sedating (reduced timidity only at doses inhibiting locomotion) while nitrazepam, oxazepam, diazepam and chlordiazepoxide were less sedating (reduced timidity at non-sedative doses, stimulated social investigation and locomotion). Only drugs stimulating GABA-receptor complex (benzodiazepines, barbiturates and GABAergic drugs) inhibited active escapes and defenses at doses lower than those reducing attacks. This suggests that the GABA-receptor complex is involved in regulation of defensive-escape tendency in intraspecies conflict.

Aggression↗