Search results for "MUCOSA"
showing 10 items of 1066 documents
Permeability of the bladder mucosa to thiotepa, adriamycin, and daunomycin in men and rabbits.
1976
The permeability of the bladder mucosa to thiotepa and to the anthraquinonic antibiotics, adriamycin and daunomycin, was investigated both in humans and in experimental animals. Instillations in rabbits were performed either in intact males or in animals with ligated ureters. Absorption of thiotepa was significantly higher than that of the antibiotics both in men and in rabbits. Furthermore, a qualitative difference was observed in rabbits in relation to time and with regard to fixation to vesical tissues. In man, absorption was highest after transurethral surgery. It was also increased in cases with extensive anaplastic tumours or in the presence of acute inflammatory reactions.
Increased airway inflammatory cells in endurance athletes: what do they mean?
2003
Inflammatory cells are increased in the airways of endurance athletes, but their role in causing exercise-induced respiratory symptoms and bronchoconstriction, or their possible long-term consequences, are uncertain.To put the results of athlete studies in perspective, by analysing the pathogenesis of airway cell changes and their impact on respiratory function.Athletes of different endurance sports at rest showed increased airway neutrophils. Elite swimmers and skiers also showed large increases in airway eosinophils and lymphocytes, possibly related to chronic, exercise-related exposure to irritants or cold and dry air, respectively. Post-exercise studies reported variable responses of ai…
The renin–angiotensin system in gastrointestinal functions
2023
In this chapter, we describe the role played by classical and alternative renin–angiotensin system (RAS) in the physiological regulation of gastrointestinal functions. RAS modulates gut motility and mucosal functions, including secretion, fluid, and nutrient absorption. We focus mainly on the activation of angiotensin II type 1 and 2 receptors located on the smooth muscle and epithelial cells or on the enteric neurons. Few studies indicate that alternative RAS may counteract classical RAS functions. Although data on the enteric RAS system are still scarce, they encourage further investigations in consideration also of a potential involvement in gastrointestinal disorders.
Glutathione conjugation of the rabbit mammary pheromone 2-methylbut-2-enal
2008
International audience; In the process of smell, the olfactory signal is initiated by the binding of odorous molecules to olfactory receptors. In the receptor environment,associated events are supposed to modulate this signal.Thus, the xenobiotic metabolizing enzymes, potentially involved in the clearance of the odorous molecules, could modulate the availability of these molecules for the olfactory receptors, and consequently could participate indirectly in the olfactory signal termination. A mammary pheromone, which is an odorous aldehyde (2-methylbut-2-enal or 2MB2) has been recently characterized in the rabbit by our group. The aim of this work was to elucidate the metabolism of 2MB2 in …
Activity and expression of drug metabolizing enzymes in olfactory mucosa of rats treated by hepatic inducers
2008
International audience; Several drug-metabolizing enzymes (DME), such as cytochrome P450- dependent monooxygenases (CYP) and transferases have been characterized in the olfactory epithelium. Some of them are preferentially expressed in this tissue, while others are similar to those present in the liver. The role of these enzymes remains unclear. Since the olfactory mucosa is in direct contact with the external environment, these enzymes can contribute to the detoxification of chemical compounds. In addition, these enzymes could be involved in the olfaction process, especially in the biotransformation of odorants. Indeed, the rapid inactivation and clearance of odorants is a prerequisite for…
Acute effects of 1,1,1-trichloroethane on human olfactory functioning.
2004
Background Animal experiments indicate that 1,1,1-trichloroethane can cause degeneration of the olfactory epithelium. The effects of 1,1,1-trichloroethane on human odor perception still have not been investigated. The goal of this study was to learn more about acute effects of 1,1,1-trichloroethane. Methods Twelve healthy, nonsmoking students were exposed to 200 and 20 ppm (control) 1,1,1-trichloroethane in an exposure chamber for 4 hours according to a crossover design. Olfactory functioning was investigated with the Sniffin’ Sticks. The test includes the determination of the detection threshold for n-butanol and an odor identification test. Results After 1 hour of exposure to 200 ppm 1,1,…
Rat olfactory bulb and epithelium UDP-glucuronosyltransferase 2A1 (UGT2A1) expression: in situ mRNA localization and quantitative analysis.
2001
UDP-glucuronosyltransferases (UGTs) form a multigenic family of enzymes involved in the biotransformation and elimination of numerous endo- and xenobiotic compounds. Beside the diverse UGT isoforms present in the liver as well as in other tissues, the UGT2A1 isoform, also called olfactory UGT, was initially thought to be expressed in the nasal epithelium only. In this work, we demonstrate the UGT2A1 mRNA expression in the olfactory bulb, using in situ hybridization and quantitative reverse transcription-polymerase chain reaction (RT-PCR) techniques. Within the epithelium, UGT2A1 mRNA is mainly found in the sustentacular cells and to a lesser extent in Bowman's gland cells. Moreover, in situ…
Role of the vomeronasal system in intersexual attraction in female mice
2008
Although it is generally accepted that rodents' sociosexual behavior relies mainly on chemosignals, the specific roles played by the vomeronasal and olfactory systems in detecting these signals are presently unclear. This work reports the results of three experiments aimed at clarifying the role of the vomeronasal system on gender recognition and intersexual attraction, by analyzing the effects of lesions of the accessory olfactory bulbs (AOB) in chemically naive female mice. The first experiment demonstrates that lesions of the AOB abolish the preference that females show for male-soiled bedding in tests in which the females can contact the bedding, thus having access to both volatile and …
Essential Oils and Pure Volatile Compounds as Potential Drugs in Alzheimer's Disease Therapy: An Updated Review of the Literature
2016
Background: The use of aromatic plants to relief different illness is not a new therapy. Actually aromatic plants have been used for many centuries by different cultures around the world. Pharmacological studies provide scientific support to the traditional use of aromatic medicinal plants and aromatherapy; nevertheless, more clinical trials are required regarding to their effectiveness in order to establish a guidance for their use in routine healthcare. Moreover, modern medicine in studies about olfactory function has attained great achievements and got Nobel Prize in 2004. These new searches have obviously fueled interest in the essential oils and volatile compounds of natural origin. Se…
Synaptogenesis in the mouse olfactory bulb during glomerulus development
2008
Synaptogenesis is essential for the development of neuronal networks in the brain. In the olfactory bulb (OB) glomeruli, numerous synapses must form between sensory olfactory neurons and the dendrites of mitral/tufted and periglomerular cells. Glomeruli develop from E13 to E16 in the mouse, coincident with an increment of the neuropil in the border between the external plexiform (EPL) and olfactory nerve layers (ONL), coupled to an extensive labelling of phalloidin and GAP-43 from the ONL to EPL. We have tracked synaptogenesis in the OB during this period by electron microscopy (EM) and immunolabelling of the transmembrane synaptic vesicle glycoprotein SV-2. No SV-2 labelling or synapses we…