Deficiency of the immunoproteasome subunit β5i/LMP7 supports the anxiogenic effects of mild stress and facilitates cued fear memory in mice.

Proteolysis as mediated by one of the major cellular protein degradation pathways, the ubiquitin-proteasome system (UPS), plays an essential role in learning and memory formation. However, the functional relevance of immunoproteasomes in the healthy brain and especially their impact on normal brain function including processes of learning and memory has not been investigated so far. In the present study, we analyzed the phenotypic effects of an impaired immunoproteasome formation using a β5i/LMP7-deficient mouse model in different behavioral paradigms focusing on locomotor activity, exploratory behavior, innate anxiety, startle response, prepulse inhibition, as well as fear and safety conditioning.

Predator odour but not TMT induces 22-kHz ultrasonic vocalizations in rats that lead to defensive behaviours in conspecifics upon replay.

Predator odours induce defensive behaviour in prey animals such as rats. The present study investigated (1) whether laboratory rats exposed to predator odours emit 22-kHz calls which may have an alarming function and (2) whether playback of such calls induces behavioural changes in conspecifics. For this, Sprague-Dawley rats were exposed to samples of fox and lion urine, as well as to the synthetic predator odour TMT.

Predator odor induced defensive behavior in wild and laboratory rats: A comparative study.

Laboratory rats are frequently used as animal models in research. Since the 1920s rats are bred and reared in laboratories which affects anatomy, physiology, and behavior responses. In the present study we exposed laboratory and wild rats to predator odor and comparatively analyzed their behavioral and physiological responses.

Habenula and interpeduncular nucleus differentially modulate predator odor-induced innate fear behavior in rats.

Fear is an important behavioral system helping humans and animals to survive potentially dangerous situations. Fear can be innate or learned. Whereas the neural circuits underlying learned fear are already well investigated, the knowledge about the circuits mediating innate fear is still limited.

Predator odor exposure increases food-carrying behavior in rats.

To cover their energy demands, prey animals are forced to search for food. However, during foraging they also expose themselves to the risk of becoming the prey of predators. Consequently, in order to increase their fitness foraging animals have to trade-off efficiency of foraging against the avoidance of predation risk.

The olfactory hole-board test in rats: a new paradigm to study aversion and preferences to odors.

Odors of biological relevance (e.g., predator odors, sex odors) are known to effectively influence basic survival needs of rodents such as anti-predatory defensiveness and mating behaviors.