List of Abstracts from the XVIIIth Congress of European Chemoreception Research Organization, ECRO-2008

2008 Chemical Senses  
We typically think of sensory systems as passively generating faithful representations of external stimuli at initial, low-level stages of the nervous system and then performing increasingly complex transformations of these representations as information propagates to higher levels. Likewise, the modulation of sensory codes during behavior -for example, as a function of behavioral context or attentional state -is typically thought to occur at higher nervous system levels. This talk will discuss
more » ... recent findings from our laboratory demonstrating that, in the olfactory system, odor representations in the behaving animal can be transformed at low levels -as early as the primary sensory neurons themselves -via a variety of different mechanisms related to the active acquisition of olfactory information. First, changes in odor sampling behavior (i.e. -ÔsniffingÕ) Chem. Senses Introduction: One of the characteristics of taste disorder is that it occurs most often in aged population, and numbers of patients with taste disorders increase with age. To study the causative factors of taste disorders, we examined 408 patients. We examined therapeutic effects of a zinc agent on taste disorders by taking into account the causative factors of the disorder and age. ECRO Abstracts E3 Downloaded from by guest on 28 July 2018 Subjects: Patients with the disorder usually came to the ENT Department of Nihon University Itabashi Hospital and complained of a reduction in the sense of taste. Ages of patients ranged from 21 to 84. The therapeutic effects of treatment of taste disorder with a zinc agent were studied in 252 cases. Methods: The causative factors of the taste disorders were classified as follows: drug-induced, zinc deficiency, systemic diseases, inflammation of the upper respiratory tract, head injuries, glossitis, loss of flavor and idiopathic factors. In the taste disorders patients due to zinc deficiency the triggering mechanisms of the disorder were not known, the serum zinc concentration was low. Serum zinc concentrations lower than 69 lg/dl were considered abnormally low. Taste functions were evaluated with the filter-paper disk method and solutions of sucrose, sodium chloride and tartaric acid were tested. The zinc agent, polaprezinc, was singly given at a daily dose of 150 mg/day (75 mg, b. i. d.). Polaprezinc is a zinc-carnosine complex formulated as white odorless granules whose primary use is treatment of peptic ulcers. 75 mg of polaprezinc contains about 17 mg of zinc. Results: In the population studied, drug-induced taste disorders accounted for 32% of the causative factors, followed by taste disorders due to idiopathic factors, systemic disorders, and zinc deficiency. Among the 408 patients, 116 cases showed low serum zinc concentration, regardless of the causative factors of the taste disorder. Taste disorders observed in the aged group with a significantly higher incidence of abnormality were caused by drugs and systemic disorders. On the other hand, causative factors that were significantly lower in the aged group were idiopathic factors and inflammations of the upper respiratory tract. Zinc administration was effective in 70% of the whole population studied, and 74% in the aged population. No significant difference was observed in curative effectiveness rate among age groups. Objective: The goal of this study was to characterize features of normal and abnormal taste bud structures using confocal microscopy (CM). Materials and methods: The human tongue epithelium of 60 healthy subjects with a normal gustatory sensibility, aged 18 to 76 years, was examined in vivo by CM. A combination of the Heidelberg Retina Tomograph HRTII and Rostock Cornea Module was used. The results were compared with those of 28 patients with taste disorders. Results: Considering age and groups significant differences were found for the parameters "number of cells of taste bud" and "density" (P < 0.05). Conclusions: With CM it is basically possible to reveal the peripherally taste organ. Thus, it may serve as a helpful tool to diagnose patients with taste disorders. Recently, rigid confocal endoscopes have been developed that can obtain confocal images of the taste bud in vivo in near real time. Use of this diagnostic tool provides a high potential to image papillae and following taste bud in a clinically setting. Recently a new test for psychophysical assessment of taste function was introduced 1 . It is based on strips made from filter paper which E4 ECRO Abstracts Downloaded from by guest on 28 July 2018 were impregnated with different taste solutions (four concentrations each for sweet, sour, salty and bitter). These strips are placed on the tongue and subjects are asked to identify the taste quality. Each subject receives 4 concentrations of each taste in a pseudorandomized sequence. Results correlate significantly with the results of the well established three-drop-technique (r 69 =0.67). Repeated measures indicated good reproducibility of the results for the taste strips (r 69 =0.68). Results suggest the usefulness of this new technique in routine clinical practice. Major advantages are long shelf-life and convenience of administration. On electrophysiological level gustatory event-related potentials appear to be a well-investigated means 2,3 for clinical investigations in specific situations, e.g. medico-legal cases.
doi:10.1093/chemse/bjn083 fatcat:bna7hg4zsbebfabzwjw7o7yspy