Sensory Contact Model: Protocol, Control, Applications

Among the models that become more and more popular in behavioral neuroscience are biosocial models, which allow studying the consequences of chronic social conflicts and social stress in animals. The sensory contact model appears to represent one of such models. Repeated experience of aggression or social defeats in daily agonistic interactions in male mice of different strains leads to the formation of opposing kinds of social behavior: one attributable to winners (aggressors) and another attributable to losers (defeated males, victims of aggression). A large variety of behavioral pathologies which develop in male mice in these conditions (anxious depression, catalepsy, social withdrawal, pronounced aggression, anxiety, hyperactivity, cognitive disturbances, anhedonia etc.), which are accompanied by somatic changes (reduced gonad function, psychogenic immune deficiency etc), suggest that this approach could be used for different aims of biomedical studies. Putative mechanisms of release and maintenance of aggressive and submissive behaviors in male mice under the sensory contact model, criteria of correct application, basic experimental setups and problem of the control, methodical capabilities and potentials of the sensory contact model applications are discussed in this paper

The influence of psychoemotional status on metastasis of lewis lung carcinoma and hepatocarcinoma-29 in mice of C57BL/6J and CBA/LAC strains

Aim: To study the influence of psychoemotional status on the development of experimental lung metastases of strain-specific murine Lewis lung carcinoma in C57BL/6J mice and hepatocarcinoma-29 in CBA/Lac male mice. Materials and Methods: Sensory contact model was used for generating animals with repeated experience of social victories or defeat in daily agonistic interactions. Tumor cells were injected into the tail vein after 20 days of agressive confrontations and the number of metastases in the lung was calculated 16 days later. Results: The experimental metastasis is shown to develop differently in mice with opposing social experience: the winners of both strains had significantly less metastases in the lung than the losers. Conclusion: The results obtained indicate that psychoemotional status affects Lewis lung carcinoma and hepatocarcinoma-29 metastasis in male mice.Цель работы — исследование влияния психоэмоционального состояния на метастазирование линейноспецифических опухолей — карциномы легкого Льюис у мышей линии C57BL/6J и гепатокарциномы-29 у мышей линии CBA/Lac. Материалы и методы: для получения самцов мышей с повторным опытом социальных побед и поражений в ежедневных агрессивных взаимодействиях была использована модель сенсорного контакта (на протяжении 20 дней). Клетки опухолей вводили в хвостовую вену животных. Количество метастазов в легких подсчитывали через 16 дней после перевивки опухоли. Результаты: показано, что метастазирование в легкие протекает неодинаково у мышей с различным психоэмоциональным состоянием: у мышей с опытом побед обеих линий количество метастазов в легких было существенно меньше, чем у животных с опытом психоэмоциональных поражений. Выводы: психоэмоциональное состояние влияет на процессы метастазирования карциномы легкого Льюис и гепатокарциномы-29 у самцов мышей линий C57BL/6J и CBA/Lac

Limiting effect of diazepam on lewis lung carcinoma metastasis in anxious male mice

Aim: It has been shown previously that chronic social defeat stress produces development ofstrong anxiety and increases intensity of experimental metastasis in the losers in comparison with the winners and control mice. The question was: isit possible to decrease the number ofmetastases inthe losers by chronic or acute diazepam treatment. Materials and Methods: Sensory contact model was used for generating male mice with repeated experience of social victories or defeats in daily agonistic interactions. Tumor cells of Lewis Lung Carcinoma (LLC) were injected into the tail vein of animals after 10 days of agonistic interactions. Then mice were treated acutely or chronically (7 days) with diazepam (1 mg/kg, i. p). Number ofmetastases in the lung was calculated in 16 days after tumor cell transplantation. Results: Diazepam decreased the number of LLC metastases in anxious losers, whereas in the winners and control mice, without anxiety state, diazepam was ineffective. Conclusion: Well-known anxiolytic diazepam may decrease intensity of metastasis in anxious mice