Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “TASTE”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 163 records · Page 9Linked to original sources
PubMed1988

Assessment of the taste interaction between two qualitatively similar-tasting substances: a comparison between comparison rules.

The taste interaction between sucrose and fructose was assessed by using three different comparison procedures: the summated response comparison, the factorial plot comparison, and the equimolar comparison rule. The perceived sweetness intensities were obtained on a ratio scale by using a functional measurement approach in combination with a two-stimulus procedure. The conclusions obtained from each of the three comparison rules were identical. The taste interaction between sucrose and fructose could be explained to a large extent, but not completely, by the apparent taste "interactions" within sucrose and fructose as single substances. It is argued that the apparent taste interaction within a large number of single sugars and between two of these sugars in a mixture is somewhat synergistic at low sweetness levels, additive at intermediate sweetness levels, and suppressive at high sweetness levels.

Adolescent↗
PubMed1990

Localization of phosphatidylinositol signaling components in rat taste cells: role in bitter taste transduction.

To assess the role of phosphatidylinositol turnover in taste transduction we have visualized, in rat tongue, ATP-dependent endoplasmic reticular accumulation of 45Ca2+, inositol 1,4,5-trisphosphate receptor binding sites, and phosphatidylinositol turnover monitored by autoradiography of [3H]cytidine diphosphate diacylglycerol formed from [3H]cytidine. Accumulated 45Ca2+, inositol 1,4,5-trisphosphate receptors, and phosphatidylinositol turnover are selectively localized to apical areas of the taste buds of circumvallate papillae, which are associated with bitter taste. Further evidence for a role of phosphatidylinositol turnover in bitter taste is our observation of a rapid, selective increase in mass levels of inositol 1,4,5-trisphosphate elicited by low concentrations of denatonium, a potently bitter tastant.

Animals↗
PubMed2003

Detection of sweet and umami taste in the absence of taste receptor T1r3.

The tastes of sugars (sweet) and glutamate (umami) are thought to be detected by T1r receptors expressed in taste cells. Molecular genetics and heterologous expression implicate T1r2 plus T1r3 as a sweet-responsive receptor,and T1r1 plus T1r3,as well as a truncated form of the type 4 metabotropic glutamate receptor (taste-mGluR4),as umami-responsive receptors. Here,we show that mice lacking T1r3 showed no preference for artificial sweeteners and had diminished but not abolished behavioral and nerve responses to sugars and umami compounds. These results indicate that T1r3-independent sweet- and umami-responsive receptors and/or pathways exist in taste cells.

Animals↗
PubMed1999

Transduction for sweet taste of saccharin may involve both inositol 1,4,5-trisphosphate and cAMP pathways in the fungiform taste buds in C57BL mice.

The transduction pathways for sweet and bitter tastes were investigated with assays of inositol 1,4,5-trisphosphate (IP3) and cyclic adenosine monophosphate (cAMP) levels in mouse fungiform taste buds. Recordings of taste responses were also made in the chorda tympani nerve. Stimulation of the tongue with saccharin elicited a significant increase in IP3 levels in the fungiform papilla only at 20 mM but in cAMP levels at 3 and 20 mM, without affecting those of the nonsensory epithelial tissue. Formation of both IP3 and cAMP induced by 20 mM saccharin was suppressed by pretreatment of the tongue with pronase, a proteolytic enzyme which specifically inhibits sweet responses. Quinine and denatonium elicited both significant increases in IP3 levels at a concentration of 20 mM and slight decreases in cAMP levels at concentrations of 1-20 mM in the fungiform papilla. Recording of the chorda tympani nerve showed good responses by saccharin, quinine, and denatonium at concentrations of 1 mM and higher. These results suggest that the fungiform taste cells in C57BL mice have pronase-sensitive receptors for saccharin, coupled to both the IP3 and the cAMP pathways; the former participates only at high concentration, while the latter acts from low to high concentrations. The results also do not rule out the possibility that a phosphodiesterase-mediated cAMP decrease may be involved in bitter transduction for quinine and denatonium.

Animals↗
PubMed1998

Scanning electron microscopy of denervated taste buds in hamster: morphology of fungiform taste pores.

BACKGROUND: Taste pores of fungiform papillae are critical for taste function. Taste nerve injury affects the pore, rendering it refractory to staining with vital dyes. Whether pores of denervated fungiform papillae disappear or undergo more modest structural changes to account for diminished staining was the subject of the present study. METHODS: The chorda tympani in the hamster was served unilaterally and the anterior tongue prepared for scanning electron microscopy after 31 days of survival. RESULTS: Taste pores were found on 92% of control fungiform papillae. They were round openings formed by the free margins of keratinocytes, and centered in hillock-shaped elevations of the papillary surface. Hillocks were encircled by an indentation which, in turn, was surrounded by a circular epithelial rim. These structures associated with fungiform pores distinguish pores on the anterior tongue from those on the posterior tongue. The pores led to a channel that penetrated into the papilla. The experimental side of the tongue had markedly fewer pores. Definitive pores were present on only 53% of denervated papillae. The papillae that lacked pores either exhibited a small hillock and a subtle depression in place of the pore, or had entirely flat apical surfaces. The denervated papillae that retained pores exhibited structural changes. The pores had smaller diameters and led to shallower channels than control pores. Moreover, these persistent pores were associated with hillocks, indentations and rims that were more variable and less distinct than those of control papillae. CONCLUSIONS: Pores of fungiform papillae in hamster are associated with specialized surfaces features of the papillary epithelium. Denervation results in changes that range from disappearance of the pores to their shrinkage and the atrophy of pore-associated epithelial structures.

Animals↗
PubMed2006

Masking the taste of the conditioned taste aversion agent levamisole using an ion-exchange resin, for practical application in wildlife management.

For a conditioned taste aversion (CTA) agent to be successful in wildlife management applications, the compound must not be detectable by the animal. Levamisole is an effective CTA agent when administered by oral intubation, but it is readily detected by a number of species when mixed directly in food. This paper describes the development of an ion-exchange resin complex (resinate) to mask the taste of levamisole. Two different resins were evaluated, Amberlite IRP-64 and Amberlite IRP-69, and release studies indicated that the resinate formed using IRP-64 resin would be most suitable for use in wildlife management. Although it contained a relatively low loading of levamisole (77 g kg(-1)), the results indicated that the IRP-64 resinate should be stable in the mouth and release the levamisole quickly in the acid environment of the stomach (93% of levamisole was released into 0.1 M HCl in 5 min). In a bioassay using laboratory rats (Rattus norvegicus Berk), we showed that the taste of levamisole was successfully masked in a biscuit bait using the IRP-64 resinate and that a CTA was generated to untreated bait. The use of ion-exchange resins is a new approach in the taste-masking of CTA agents and could be applied to other wildlife management applications.

Animals↗
PubMed1995

Effect of imagining and actually tasting a sour taste on one side of the tongue.

To determine whether images can stimulate brainstem reflexes directly, parotid salivation was measured bilaterally in 24 subjects when they imagined, and actually tasted, a sour taste on one side of the tongue. Salivation increased in both cheeks during unilateral gustatory stimulation; furthermore, the response was greater on the stimulated side than contralaterally, indicating that the gustatory reflex has a unilateral component. Subjects imagined the sour taste more clearly after actually experiencing it. However, salivation did not increase significantly during imagery trials, either before or after exposure to the sour taste; in fact, salivation to imagery decreased below baseline after exposure. These findings suggest that extraneous factors (e.g. the emotional connotations of images, anxiety, discomfort, repetitive measurement or fatigue) might sometimes inhibit specific reflex activity induced by images.

Adolescent↗
PubMed1992

Naltrexone-induced aversions: assessment by place conditioning, taste reactivity, and taste avoidance paradigms.

The reinforcing/aversive properties of various doses of naltrexone (0.01, 1, and 10 mg/kg) were assessed in three experiments that employed place conditioning, taste reactivity, and taste avoidance paradigms. Naltrexone produced a place aversion and a taste aversion, but did not produce aversive taste reactivity responses, even at the highest dose (10 mg/kg) tested. This suggests that drugs that produce a place aversion do not necessarily produce a conditional dislike for a flavored solution with which they are paired.

Animals↗
PubMed1995

Rewarding drugs produce taste avoidance, but not taste aversion.

Paradoxically, drugs that animals will self-administer also produce conditioned taste avoidance at similar dosage levels. The present review presents evidence that the taste avoidance produced by these rewarding drugs differs qualitatively from the taste avoidance produced by the nonrewarding, emetic drug, lithium chloride. An analysis of data pooled across 6 experiments compares the nature of flavor-drug associations produced by various rewarding drugs (amphetamine, cocaine, methamphetamine, methylphenidate, morphine, nicotine and phencyclidine) with that produced by lithium. The data from the groups conditioned with the rewarding drugs and with lithium were combined into the two categories of low/moderate and high doses. When assessed by the CTA test, the rewarding drugs did not differ from lithium in the strength of the CTA at low/moderate or at high doses. However, when assessed by the TR test, lithium produced more prominent aversive taste reactions than did the rewarding drugs. These findings suggest that the flavor-drug association produced by lithium and rewarding drugs differs qualitatively. With the large pooled data set we also assessed the relationship among the various TR categories, resulting in two factors of "Ingestion" and "Aversion" accounting for 55% of the total variability within the data.

Animals↗
PubMed2004

Recombinant curculin heterodimer exhibits taste-modifying and sweet-tasting activities.

Curculin from Curculigo latifolia is a unique sweet protein that exhibits both sweet-tasting and taste-modifying activities. We isolated a gene that encodes a novel protein highly homologous to curculin. Using cDNAs of the previously known curculin (designated as curculin1) and the novel curculin isoform (curculin2), we produced a panel of homodimeric and heterodimeric recombinant curculins by Escherichia coli expression systems. It was revealed that sweet-tasting and taste-modifying activities were exhibited solely by the heterodimer of curculin1 and curculin2.

Amino Acid Sequence↗
PubMed2000

Serotonin reuptake is less efficient in taste aversion resistant than in taste aversion-prone rats.

We have previously reported the development of rat lines bred selectively for differences in taste aversion conditionability. Earlier studies demonstrated that the taste aversion resistant (TAR) animals exhibited lower concentrations of brain serotonin and consumed greater amounts of ethanol than their taste aversion prone (TAP) counterparts. In the present study, TAR rats demonstrated significantly less efficient brain serotonin transport compared to TAP rats, but the rat lines demonstrated similar levels of serotonin transporter or V(max) and similar whole brain paroxetine (a specific serotonin reuptake inhibitor) binding (B(max)). These results suggest that the rat lines differ in the mechanisms that transport serotonin into nerve endings, but do not differ in the binding of serotonin to the transporter or in the number of serotonin transport sites. The data support the hypothesis that genetically determined differences in the serotonin system contribute to individual differences in taste aversion conditionability. The findings further suggest that differences in serotonin transport may influence the propensity to self-administer ethanol.

Animals↗
PubMed2003

The evaluation of brain activity in response to taste stimuli--a pilot study and method for central taste activation as assessed by event-related fMRI.

BACKGROUND: Brain pathways contribute to the regulation of appetite behaviors, and advancements in brain imaging offer new opportunities in determining whether disturbances of these pathways play a role in pathological feeding behaviors in humans. We developed a standardized method for the assessment of brain activation in response to taste stimuli. METHODS: Five healthy control women were positioned in a 1.5 T GE magnet resonance (MR) scanner for functional MR imaging (fMRI). They received 1.0 cm3 samples of 1 M glucose solution or artificial saliva (25 mM KCl, 2 mM NaHCO3). Fluid challenges were delivered by a programmable syringe pump (J-Kem Scientific, St. Louis, MO). E-Prime software (Psychology Software Tools Inc., Pittsburgh, PA) coordinated taste stimulation with MR scanning. Data were analyzed using NeuroImaging software (NIS). RESULTS: Healthy women showed increased orbitofrontal cortex activation when glucose was compared to artificial saliva. In addition, mesial and lateral temporal cortical regions contrasted glucose from artificial saliva. CONCLUSIONS: This study demonstrates a design for the systematic study of brain activation after taste stimulation using fMRI and computer controlled stimulus delivery. The results are consistent with previous studies, showing activation in higher order brain centers that are involved in emotional coding of taste experience.

Adult↗
PubMed2000

Taste active compounds in a goat cheese water-soluble extract. 2. Determination of the relative impact of water-soluble extract components on its taste using omission tests.

The aim of this work was to determine the relative impact of water-soluble compounds on the gustatory properties of a goat cheese water-soluble extract (WSE). Using a semisynthetic model mixture (MWSE) previously elaborated in physicochemical and gustatory accordance with the cheese WSE (see part 1, Engel et al. J. Agric. Food Chem. 2000, 48, 4252-4259), omission tests were performed. Among the main taste characteristics of the WSE (salty, sour, and bitter), saltiness was explained by an additive contribution of sodium, potassium, calcium, and magnesium cations, whereas sourness was mainly due to a synergistic effect involving sodium chloride, phosphates, and lactic acid and bitterness was found to result from calcium and magnesium chlorides, the impact of which was partially masked by sodium chloride. In contrast, amino acids, lactose, and peptides did not have any significant impact on WSE taste properties. To quantify the contribution of the taste active compounds to bitterness and saltiness, stepwise multiple linear regressions were performed. Those contributions were expressed as a percentage of the considered taste characteristic intensity in the WSE. The model obtained allowed up to 97.4% of the perceived saltiness to be described and approximately 85% of the bitterness.

Animals↗
PubMed1984

Neonatal ablations of the gustatory neocortex in the rat: taste aversion learning and taste reactivity.

Rats sustaining ablations of gustatory neocortex (GN) at 2, 10, 20, or 60 days of age were compared with control rats in the acquisition and extinction of a learned taste aversion; in addition, these rats were tested for taste preference across five concentrations of sodium chloride solution. Results indicated that GN ablation disrupted aversion acquisition and extinction regardless of age at surgery. Taste response functions for the sodium chloride solutions shown by all GN groups of rats mirrored those of control rats: preference (relative to water baseline) for middle concentrations and rejection of the strongest salt concentration. There was a suggestion that the 20- and 60-day-old GN rats were hyperresponsive to the suprathreshold concentrations of NaCl (except the strongest concentration). The increased response to salt solutions in the 20- and 60-day GN rats may have been related to the significant decreases in water consumption relative to that of normal rats. Water consumption of control rats and GN rats in the 2-day and 10-day groups was essentially equal. It is concluded that infant ablation of the GN does not spare normal taste aversion learning and that rats with GN ablations, regardless of age at surgery, respond in a normal manner to the hedonic aspects of sodium chloride solutions.

Age Factors↗
PubMed1982

Cortical substrates of taste aversion learning: dorsal prepiriform (insular) lesions disrupt taste aversion learning.

The functional relation between restricted damage to ventral primary somatosensory neocortex and the ability of rats to acquire conditioned taste aversion (CTA( was examined by a combination of behavioral and neurohistological techniques. Lesions confined exclusively to the established gustatory neocortex (GN) did not disrupt CTA acquisition, nor did lesions confined to suprarhinal cortical areas ventral to the GN. Lesions that encroached on dorsal prepiriform and insular cortices produced CTA acquisition deficits and damaged a large proportion of efferent projections to the prefrontal and precentral neocortex. In a second experiment, lesions of dorsal prepiriform and insular cortices did not modify taste preference-aversion threshold to any of the four taste modalities. It is concluded tha ventral somatosensory neocortical fields, including the established GN, do not mediate CTA acquisition and that rhinal cortices ventral and posterior to the GN are preferentially involved in associative learning for tastes and illness.

Animals↗
PubMed1998

Recalling sweet taste intensities in the presence and absence of other tastes.

Memory for sweet taste intensities in different media during 125 h was investigated using three concentrations (w/w) of sucrose: 4.21% (0.125 M), 8.28% (0.25 M) and 16.06% (0.5 M). Sucrose was dissolved in four media [water with no tastant and water with 0.73% (0.125 M) sodium chloride, 0.04% (0.002 M) citric acid and 0.04% (0.002 M) caffeine] as standard stimuli. Subjects (n = 39) were assigned into four groups, each group performing the memory task in one medium only. After tasting each standard the subjects reproduced the subjective taste intensity immediately and after 12 min and 1, 5, 25 and 125 h by mixing portions of low (0%) and high (29.75%; 1 M) concentrations (w/w) of sucrose and by tasting and retasting (ad libitum procedure). The produced sucrose concentrations increased significantly from the first session to the 125 h time interval. There was a significant difference between immediately reproduced standard concentrations and concentrations produced after all time intervals. Relative differences from standard (delta i/i) differed only between concentrations produced immediately and after 125 h time interval. The low (4.21%) concentration showed larger differences from standard than the high (16.06%) concentration. The added tastant had no effect on the results.

Adult↗
PubMed1980

Recall (versus recognition) of taste and immunization against aversive taste anticipations based on illness.

Two experiments show that, after taste-aversion conditioning, rats can use external retrieval cues to recall or anticipate the aversive taste solution and avoid its location without making contact with the flavor. They also show that the rat's avoidance of a conditioned aversive taste and its consumption of the aversive flavored solution can be attenuated by giving it prior runway training in which taste reward is given inconsistently on a partial reinforcement schedule.

Animals↗
PubMed2006

Taste discrimination in conditioned taste aversion of the pond snail Lymnaea stagnalis.

Conditioned taste aversion (CTA) in the pond snail Lymnaea stagnalis has been widely used as a model for gaining an understanding of the molecular and behavioral mechanisms underlying learning and memory. At the behavioral level, however, it is still unclear how taste discrimination and CTA interact. We thus examined how CTA to one taste affected the feeding response induced by another appetitive food stimulus. We first demonstrated that snails have the capacity to recognize sucrose and carrot juice as distinct appetitive stimuli. We then found that snails can become conditioned (i.e. CTA) to avoid one of the stimuli and not the other. These results show that snails can distinguish between appetitive stimuli during CTA, suggesting that taste discrimination is processed upstream of the site where memory consolidation in the snail brain occurs. Moreover, we examined second-order conditioning with two appetitive stimuli and one aversive stimulus. Snails acquired second-order conditioning and were still able to distinguish between the different stimuli. Finally, we repeatedly presented the conditional stimulus alone to the conditioned snails, but this procedure did not extinguish the long-term memory of CTA in the snails. Taken together, our data suggest that CTA causes specific, irreversible and rigid changes from appetitive stimuli to aversive ones in the conditioning procedure.

Animals↗