Comparative Fear-Related Behaviors to Predator Odors (TMT and Natural Fox Feces) before and after Intranasal ZnSO4 Treatment in Mice

The possibility that synthetic 2,4,5-trimethylthiazoline (TMT), frequently used to induce unconditioned fear in rodents, could be more a pungent odor activating intranasal trigeminal nerve fibers rather than a predator odor index is currently discussed. In order to explore this question, the present study compared fear-related behaviors to predator odors (synthetic 10% TMT and natural fox feces) and toluene (as an irritant compound without ecological significance) before and after intranasal ZnSO4 perfusion which is known to provoke transient anosmia. Results show that natural fox feces could be consider as a pure olfactory (CN I) nerve stimulant while 10% TMT appeared to be a mixed olfactory (CN I) and trigeminal (CN V) nerves stimulant with a great olfactory power and a low trigeminal power. These findings suggest that behavioral neuroscience studies should use concentrations lower than 10% TMT to obtain fear-related behaviors similar to those obtained with natural fox feces odor

Les salariés des exploitations agricoles dans les élections aux Chambres d’agriculture

Les élections aux Chambres d’agriculture des représentants du collège des salariés d’exploitations agricoles sont beaucoup plus mal connues que celles du collège des chefs d’exploitation. Or la place du salariat progresse à nouveau dans le travail agricole. Les tableaux présentés fournissent les résultats complets par départements de 1989 à 1995.Polling for agriculture wage earner’s representatives Polling for Chambres d’agriculture’s cultivators deputies are closely studied. On the opposite, polling for agriculture wage earner’s representatives are almost ignored though their place is growing in agricultural employment. These charts give detailed figures at departement level for 1989’s and 1995’s polls

Identification of pyridine analogs as new predator-derived kairomones.

In the wild, animals have developed survival strategies relying on their senses. The individual ability to identify threatening situations is crucial and leads to increase in the overall fitness of the species. Rodents, for example have developed in their nasal cavities specialized olfactory neurons implicated in the detection of volatile cues encoding for impending danger such as predator scents or alarm pheromones. In particular, the neurons of the Grueneberg ganglion (GG), an olfactory subsystem, are implicated in the detection of danger cues sharing a similar chemical signature, a heterocyclic sulfur- or nitrogen-containing motif. Here we used a "from the wild to the lab" approach to identify new molecules that are involuntarily emitted by predators and that initiate fear-related responses in the recipient animal, the putative prey. We collected urines from carnivores as sources of predator scents and first verified their impact on the blood pressure of the mice. With this approach, the urine of the mountain lion emerged as the most potent source of chemical stress. We then identified in this biological fluid, new volatile cues with characteristic GG-related fingerprints, in particular the methylated pyridine structures, 2,4-lutidine and its analogs. We finally verified their encoded danger quality and demonstrated their ability to mimic the effects of the predator urine on GG neurons, on mice blood pressure and in behavioral experiments. In summary, we were able to identify here, with the use of an integrative approach, new relevant molecules, the pyridine analogs, implicated in interspecies danger communication

inhalation exposure to acetone induces selective damages on olfactory meuroepithelium in mice

International audienc

inhalation exposure to acetone induces selective damages on olfactory meuroepithelium in mice

International audienc

Postnatal exposure to predator odor induces modification in fear-related behaviors at adulthood without changers in corticosterone levels

Environmental stimuli and adverse experiences in early life may result in behavioral and physiological changes in adulthood. In several animal species, the odors cues are crucial in the setting of adaptive behaviors, especially towards predators. However, little is known about the effects of postnatal exposure to predator odor on the later physiological and behavioral responses to this natural stressor. Thus, the aim of this study was to investigate the effects of a postnatal exposure to synthethic predator odor (TMT) in mice pups on later adult fear-related behaviors and corticosterone levels in response to this specific stimulus. Compared to pups only postnatally exposed to water, results showed that behavioral responses were significantly different in the group of mice exposed to TMT, i.e. a decrease of fear-related behaviors while no differences occurred in the corticosterone levels between both groups

Postnatal exposure to predator odor induces modification in fear-related behaviors at adulthood without changers in corticosterone levels

Environmental stimuli and adverse experiences in early life may result in behavioral and physiological changes in adulthood. In several animal species, the odors cues are crucial in the setting of adaptive behaviors, especially towards predators. However, little is known about the effects of postnatal exposure to predator odor on the later physiological and behavioral responses to this natural stressor. Thus, the aim of this study was to investigate the effects of a postnatal exposure to synthethic predator odor (TMT) in mice pups on later adult fear-related behaviors and corticosterone levels in response to this specific stimulus. Compared to pups only postnatally exposed to water, results showed that behavioral responses were significantly different in the group of mice exposed to TMT, i.e. a decrease of fear-related behaviors while no differences occurred in the corticosterone levels between both groups

Postnatal exposure to predator odor (TMT) enhances spatial learning in mice adulthood.

International audienceAdult behavioral and physiological responses are partly dependent on neonatal experiences. In several animal species, enriched/aprovished environments and stressful/appeasing events are crucial in the setting of adaptative behaviors. However, little is known about the effects of postnatal exposure to predator odor (as unconditioned fear-related stimulus) on spatial learning at adulthood. Thus, the aim of the present study was to investigate the effects of a postnatal exposure to 2,4,5-trimethylthiazoline (TMT, as a predator odor) on radial arm maze (RAM), Tolman maze (TM) and Morris water maze (MWM) in mice at adulthood. The results showed that a TMT group constituted by mice exposed postnatally during 3 weeks to TMT presented significantly better spatial learning achievements in adulthood compared to a water group, postnatally exposed to water only, as well as compared to a butanol group (butanol used as an odor without ecological significance) exposed postnatally to butanol during 3 weeks

Postnatal exposure to synthetic predator odor (TMT) induces quantitative modification in fear-related behaviors during adulthood without change in corticosterone levels.

International audienceEnvironmental stimuli and adverse experiences in early life may result in behavioral and physiological changes in adulthood. In several animal species, the odors cues are crucial in the setting of adaptive behaviors, especially towards predators. However, little is known about the effects of postnatal exposure to predator odor on the later physiological and behavioral responses to this natural stressor. Thus, the aim of this study was to investigate the effects of a postnatal exposure to synthetic predator odor (TMT) in mice pups on later adult fear-related behaviors and corticosterone levels in response to this specific stimulus. Pups postnatally exposed to only water showed later in adult life behavioral responses when exposed to TMT that were statistically different from mice that were exposed as neonates to TMT. In addition, mice exposed as neonates to TMT showed a decrease of fear-related behaviors while no differences occurred in the corticosterone levels between both groups