Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0235290 (bitter taste)
 1,408 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The relationships among suprathreshold taste responses to acesulfame-K, Na-saccharin and 6-n-propylthiouracil (PROP) were examined in two studies. In the first study, the labeled magnitude scale was used with the high anchor labeled as 'strongest imaginable oral sensation' and in the second study, it was labeled as 'strongest imaginable sensation of any kind'. Results from the two procedures were similar. Individual differences among 65 subjects were seen in bitter responses to acesulfame-K and saccharin. Bitter responses to acesulfame-K ands accharin were positively correlated, but showed no significant relationship with responses to PROP bitterness or with PROP taster groups. Saccharin and acesulfame-K may share a common mechanism for bitter taste reception and transduction, one that varies across individuals and is different from mechanisms mediating bitter responses to PROP. Changing the instructions of the labeled magnitude scale induced a context effect. Ratings of sweetness referenced to the 'strongest imaginable sensationof any kind' were lower than ratings referenced to just oral sensations.
 ...
PMID:Bitter taste of saccharin and acesulfame-K. 1175 65

Foraging behavior is an expression of learning, context, and experience arising from integration of sensory information obtained during feeding with postingestive consequences of food ingestion. Although it has been well established that gustatory and olfactory systems of the mouth and nose provide sensory information to the consumer (in the form of flavor), sweet and bitter taste receptors have recently been identified in the intestinal tract of humans and rodents. It remains possible that sensory information generated in the gut could contribute to the learning process. Thus, a series of experiments was conducted to determine if classical associative learning occurs when the conditional stimulus circumvents oronasal presentation via direct delivery to the gut or peritoneal cavity. Mice receiving an intragastric infusion of 5 mM sodium saccharin immediately followed by LiCl administration demonstrated a significant decrease in preference for 5 mM saccharin in 4 consecutive 23 h, 2-bottle preference tests versus water (P = 0.0053). Saccharin was highly preferred in mice receiving intragastric (IG) saccharin only or interperitoneal (i.p.) injection of LiCl only. This reduced preference indicated that mice "tasted" saccharin infused into the gut. However, efforts to replicate with a reduced infusion volume failed to result in decreased preference. To understand if there were alternative pathways for oral detection of infused saccharin, mice received intragastric infusions (5.4 mM) and i.p. injections (10.8 mM) of sodium fluorescein. Fluorescence was observed from the tongues and esophagi of mice infused with volumes of 0.5 mL or more or injected with volumes of 0.25 mL or greater. Interperitoneal injections of 5 mM saccharin in mice resulted in reduced preference for 5 mM saccharin presented orally in 2-bottle preference tests (P = 0.0287). Oral delivery of a 500-fold less concentration of saccharin (0.01 mM) during conditioning resulted in a similar preference expression as shown in the initial IG experiment. These results demonstrate that although compounds may be tasted in the mouth absent of oral contact, associative learning is attenuated. Therefore, intestinal taste receptors are unlikely to participate directly in learning and recognition of foods during foraging events.
 ...
PMID:Do gastrointestinal taste receptors contribute to associative learning and foraging behavior? 2282 11