Search results for "OLFACTORY"
showing 10 items of 319 documents
Short-term impact of a Western diet on the physiology of the peripheral olfactory system
2016
Current feeding behaviors contribute to the epidemic levels of obesity and diabetes observed in Europe and worldwide. Both the quantity and the quality of ingested food are incriminated. Together with other sensory modalities, olfaction is involved in the control of food intake. Olfactory cues can influence eating behaviors, yet the nutritional status and diet can also alter olfactory abilities. Patients with metabolic disorders present impaired olfactory sensitivity which could in turn worsen their eating behaviors.Here we examined the short-term impact of a Western diet enriched in fat and sugar (High Fat High Sugar, HFHS) on the anatomy and physiology of the olfactory epithelium of postn…
Enzymatic systems involved in peri-receptor events of olfaction in mammalian: evolutionary perspectives
2021
International audience; The olfactory epithelium is continuously exposed to exogenous chemicals, including compounds bearing odor activity. Organisms have developed multiple mechanisms for the protection of this epithelium, among which anti-microbial proteins, enzymes fighting the oxidative stress and xenobiotic metabolizing enzymes. Our approach consists in characterizing by immunohistochemistry and mass spectroscopy analysis the proteome of the nasal mucus in different mammals (currently including Harbour porpoise, Homo sapiens, Mus musculus, Oryctolagus cuniculus, Rattus norvegicus). These analyses reveal core some enzyme families in the different species investigated, including glutathi…
Orosensory Perception of Dietary Lipids in Mammals
2008
Obesity constitutes a major public health problem for the twenty-first century, with its epidemic spread worldwide, particularly in children. The overconsumption of fatty foods greatly contributes to this phenomenon. Rodents and humans display a spontaneous preference for lipid-rich foods. However, the molecular mechanisms underlying this pattern of eating behaviour in mammals remain unclear. The orosensory perception of dietary lipids was long thought to involve only textural and olfactory cues. Recent findings challenge this limited viewpoint, strongly suggesting that the sense of taste also plays a significant role in dietary lipid perception and might therefore be involved in the prefer…
Olfactory and cortical projections to bulbar and hippocampal adult-born neurons
2015
New neurons are continually generated in the subependymal layer of the lateral ventricles and the subgranular zone of dentate gyrus during adulthood. In the subventricular zone, neuroblasts migrate a long distance to the olfactory bulb where they differentiate into granule or periglomerular interneurons. In the hippocampus, neuroblasts migrate a short distance from the subgranular zone to the granule cell layer of the dentate gyrus to become granule neurons. In addition to the short-distance inputs, bulbar interneurons receive long-distance centrifugal afferents from olfactory-recipient structures. Similarly, dentate granule cells receive differential inputs from the medial and lateral ento…
Pigmented esthesioneuroblastoma showing dual differentiation following transplantation in nude mice
1989
Esthesioneuroblastoma (ESTH) is a neuroepithelial-cell-derived neoplasm of the olfactory mucosa composed of homogeneous small round cells which contain neurosecretory granules. Melanin has been detected in such tumours only occasionally. Here we describe a new case of ESTH with divergent differentiation. The primary neoplasm was found in a 67 year-old female, involving the left nasal and maxillary sinus; she died of cerebral metastasis ten months after diagnosis. Histologically only small round cells were seen, with S-100 and NSE positivity. Electron microscopy revealed neurosecretory granules and filaments, as well as the occasional presence of melanosomes. A nude mice xenograft line has b…
Cocaine and MDMA Induce Cellular and Molecular Changes in Adult Neurogenic Systems: Functional Implications
2011
The capacity of the brain to generate new adult neurons is a recent discovery that challenges the old theory of an immutable adult brain. A new and fascinating field of research now focuses on this regenerative process. The two brain systems that constantly produce new adult neurons, known as the adult neurogenic systems, are the dentate gyrus (DG) of the hippocampus and the lateral ventricules/olfactory bulb system. Both systems are involved in memory and learning processes. Different drugs of abuse, such as cocaine and MDMA, have been shown to produce cellular and molecular changes that affect adult neurogenesis. This review summarizes the effects that these drugs have on the adult neurog…
Induction of c-fos gene expression by the selective sigma receptor ligand EMD 57445 in rat brain.
1996
Based on animal studies it has been reasoned that ligands to sigma binding sites might be effective in the treatment of schizophrenic disorders and may also be used to investigate this largely elusive disorder on a molecular level. Expression patterns of c-fos in rat brain were studied following treatment with single doses of the sigma ligand EMD 57445 (0.3, 1, 3, 30 mg/kg s.c.). Specific c-fos gene expression was detected at all concentrations tested in various cortical areas. The signals observed were dose-dependent with the highest intensities in the piriform cortex. Strong signals were also detected in hippocampal areas CA 1,2,3 and the gyrus dentatus, as well as in the medial habenula …
Objective measures of nasal function
1995
Numerous techniques to objectively measure nasal function are available to the rhinologic surgeon. Rhinomanometry, acoustic rhinometry, laser Doppler flowmetry, saccharin transport time, determination of ciliary beat frequency, and olfactory and trigeminal event-related potentials are all techniques in current use. Rhinomanometry is the standard clinical tool used to indicate those patients complaining of nasal obstruction who are likely to benefit from septal and turbinate surgery. Acoustic rhinometry permits the precise localization of nasal stenoses and is the best predictor of a patient's postoperative satisfaction. It is, in addition, more sensitive than rhinomanometry in recording cha…
Regulation of NT Receptors after Chronic Treatment with Typical and Atypical Neuroleptic Drugs
1991
Neurotensin is a tridecapeptide, which produces central effects such as hypotension, hypothermia, muscle relaxation, analgesia, antinociception, and reduces locomotor activity (Nemeroff et al., 1977). In the recent years, several lines of evidences indicated the great importance of the dopamine (DA)- neurotensin (NT) interaction taking place mostly in the mesolimbocortical areas, both at cell bodies (A10 DA-ergic group located in the ventral tegmental area -VTA-) and nerve terminal level (cerebral cortex, n. accumbens, olfactory tubercle, ventral n. caudato-putamen) (Quirion, 1983; Nemeroff, et al., 1984; Nemeroff, 1986). Immunocytochemical data indicated the presence of NT-like immunoreact…
Newborn rabbit responsiveness to the mammary pheromone is concentration-dependent.
2004
The effect of the intensity of odour signals has rarely been investigated in the regulation of odour-guided behaviour in young mammals. This series of experiments used the mammary pheromone (MP) of the female rabbit to assess the influence of stimulus concentration on neonatal pup responsiveness. The MP is a single compound isolated from rabbit milk that releases in pups the typical head searching and oral seizing behaviour. The pups (n = 621) were exposed to graded concentrations of the MP in bioassays varying in stimulus delivery conditions. Experiment 1 demonstrated that in aqueous dilutions the MP efficiently elicits behavioural responses only within a limited range of concentrations (f…