Search results for "olfaction"
showing 10 items of 251 documents
Réactivité chimiosensorielle et alimentation de l'enfant atteint de handicap
2010
ISSN : 0291-0233 ; http://www.medecine-et-enfance.net/
Perception du goût : sommes-nous tous égaux ?
2010
National audience; Les sens olfactifs et gustatifs jouent un rôle essentiel dans le comportement alimentaire. L'être humain est capable de percevoir des milliers de composés odorants grâce à un système de codage combinatoire impliquant environ 340 récepteurs olfactifs. Les récepteurs olfactifs sont sujets à un important polymorphisme génétique susceptible d'induire différentes perceptions de certaines odeurs. La perception des molécules sapides implique un nombre beaucoup plus restreint de récepteurs dont certains restent encore à découvrir. Un polymorphisme génétique à l'origine de variations importantes dans les seuils de perception de certains composés sapides affecte également les récep…
Explorer le lien entre odorat et appétit, pour mieux lutter contre la dénutrition
2020
Drosophila adult and larval pheromones modulate larval food choice
2014
Insects use chemosensory cues to feed and mate. In Drosophila , the effect of pheromones has been extensively investigated in adults, but rarely in larvae. The colonization of natural food sources by Drosophila buzzatii and Drosophila simulans species may depend on species-specific chemical cues left in the food by larvae and adults. We identified such chemicals in both species and measured their influence on larval food preference and puparation behaviour. We also tested compounds that varied between these species: (i) two larval volatile compounds: hydroxy-3-butanone-2 and phenol (predominant in D. simulans and D. buzzatii , respectively), and (ii) adult cuticular hydrocarbons (CHs). Dro…
Psychobiological effects of perinatal exposure to odorants in mice. Part II: Behavioural alteration
2010
Early exposure to odorants pre-, post- or transnatally is known to. result in a decreased avoidance or increased preference for these. odorants in mammals. There are also indications that olfactory sensitivity. for these odorants can be affected. We exposed C57-Bl/6. mice of Mor23-GFP and M71-GFP lines to lyral (LY) or acetophenone. (AC), respectively, either transnatally through the water of the. mother (1*10-5 M) or postnatally in air for 1 hr per day (20 ll pure). Animals were weaned on postnatal day 20 (P20), and 3 tests were. performed:. 1) A 3-min exploration test on P20 in a rectangular arena presenting. LY and AC under a wire mesh to measure the time spent in each. half of the arena…
Zur Bedeutung des Geruchssinnes beim Nahrungserwerb von Kröten (Amphibia, Anura, Bufonidae): Versuche mit der Kreuzkröte (Bufo calamita Laur.)
1975
The influence of olfactory and visual prey stimuli on the feeding behaviour of toads was studied as well as their response to lasting olfactory cues. A further aim was to find simple methods for testing olfactory responsiveness in anurans. Subjects were 8 adult specimens of the European species Bufo calamita (natterjack) kept in captivity one year at least. The results point to the role of olfaction in these animals.
Évaluation neuro-éthologique du comportement alimentaire olfacto-guidé du lapin nouveau-né
2012
Le document qui a justifié la délivrance du diplôme est en cours de traitement par la bibliothèque de l'établissement de soutenance.; L'olfaction est une sensorialité essentielle aux mammifères, dès les stades les plus précoces du développement. Ainsi, chez le lapin européen (Oryctolagus cuniculus), les nouveau-nés interagissent avec la mère et s'orientent vers ses tétines suite à la perception de signaux odorants appris périnatalement, ou d'au-moins un signal à l'action prédisposée, la phéromone mammaire (PM; molécule contenue dans le lait de lapine). La PM est très fortement réactogène au cours des 15 premiers jours postnatals, période d'alimentation lactée exclusive. Elle déclenche alors…
Granger Causality Analysis of Transient Calcium Dynamics in the Honey Bee Antennal Lobe Network
2023
Odorant processing presents multiple parallels across animal species, and insects became relevant models for the study of olfactory coding because of the tractability of the underlying neural circuits. Within the insect brain, odorants are received by olfactory sensory neurons and processed by the antennal lobe network. Such a network comprises multiple nodes, named glomeruli, that receive sensory information and are interconnected by local interneurons participating in shaping the neural representation of an odorant. The study of functional connectivity between the nodes of a sensory network in vivo is a challenging task that requires simultaneous recording from multiple nodes at high temp…
2019
The olfactory epithelium is continuously exposed to exogenous chemicals, including odorants. During the past decade, the enzymes surrounding the olfactory receptors have been shown to make an important contribution to the process of olfaction. Mammalian xenobiotic metabolizing enzymes, such as cytochrome P450, esterases and glutathione transferases (GSTs), have been shown to participate in odorant clearance from the olfactory receptor environment, consequently contributing to the maintenance of sensitivity toward odorants. GSTs have previously been shown to be involved in numerous physiological processes, including detoxification, steroid hormone biosynthesis, and amino acid catabolism. The…