Sense of taste in a new world monkey, the common marmoset: recordings from the chorda tympani and glossopharyngeal nerves.

Whole nerve, as well as single fiber, responses in the chorda tympani proper (CT) and glossopharyngeal (NG) nerves of common marmosets were recorded during taste stimulation with three salts, four acids, six bitter compounds and more than 30 sweeteners. We recorded responses of 49 CT and 41 NG taste fibers. The hierarchical cluster analysis distinguished three major clusters in both CT and NG: S, Q, and H.

Gustatory responses of pigs to sixty compounds tasting sweet to humans.

The gustatory responses of pigs to 60 compounds perceived as sweet by humans were studied via a semi-quantitative behavioural method derived from the Richter two-bottle preference test. Among the 60 compounds tested 35 are effective in pigs, but with an effectiveness much lower in pigs than in humans. Lugduname and carrelame, which are the two most potent sweeteners in humans, are also the most effective compounds in pigs.

New hypotheses for the GPCR 3D arrangement based on a molecular model of the human sweet-taste receptor.

A molecular model of the human sweet-taste receptor has been inferred from superpositions of 3D maps of sweetener interaction sites (themselves previously deduced from extensive structure-activity relationship studies on highly potent sweeteners) onto three well-known G protein-coupled receptors (GPCRs)-rhodopsin, beta(2)- and alpha(2A)-adrenergic receptors-assumed to be linked by common evolutionary origins. The model gives new answers to old questions on the GPCR 3D structure, such as on the orientation and arrangement of the binding helices, their interaxial distances, radial orientations and relative heights. The model should be useful as a new approach to the rational design of drugs.

Responses of the ant Lasius niger to various compounds perceived as sweet in humans: a structure-activity relationship study.

A behavioural study on the ant Lasius niger was performed by observing its feeding responses to 85 compounds presented in a two-choice situation (tested compound versus water control or sucrose solution). Among these compounds, only 21 were phagostimulating: six monosaccharides (D-glucose, 6-deoxy-D-glucose, L-galactose, L-fucose, D-fructose, L-sorbose), four derivatives of D-glucose (methyl alpha-D-glucoside, D-gluconolactone and 6-chloro- and 6-fluoro-deoxy-D-glucose), five disaccharides (sucrose, maltose, palatinose, turanose and isomaltose), one polyol glycoside (maltitol), three trisaccharides (melezitose, raffinose and maltotriose) and two polyols (sorbitol and L-iditol). None of the 16 non-carbohydrate non-polyol compounds tested, although perceived as sweet in humans, was found to be active in ants.

Taste preference in nonhuman primates to compounds sweet in man.

Primates have stimulated more interest than any other group as humans are ranked in this same mammalian order. Gustatory responses of human and nonhuman primates have already been compared for compounds such as monosaccharides, oligosaccharides, polyols, amino acids, dipeptides, proteins, dihydrochalcones, sulfamates, saccharin, acesulfame, diterpenes or urea derivatives, all known to be sweet in man. But no rational comparison in primates has been attempted.

Behavioral and single chorda tympani taste fiber responses in the common marmoset, Callithrix jacchus jacchus.

Gustatory responses of the common marmoset were studied using single fiber recordings from chorda tympani (CT) nerve and two bottle preference (TBP) tests. Hierarchical cluster analysis of 43 fibers' response profiles revealed 3 major clusters of fibers characterized by predominant sensitivity to sweeteners (S cluster), bitter compounds (Q cluster) or acids (H cluster). NaCl as well as LiCl did not stimulate CT taste fibers.

Gustatory responses of the hamster Mesocricetus auratus to various compounds considered sweet by humans.

The taste of 30 compounds was studied in the golden hamster with three different methods: single-fiber recordings, two-bottle preference (TBP), and conditioned taste aversion (CTA) tests. On the whole, the results showed that the sense of taste in the hamster differs in many respects from that in humans because, of 26 tested compounds known as sweet to humans, 11 had no taste or tasted differently. The results also supported the notion that activity in S-fibers elicits liking and activity in Q- or H-fibers rejection.

Evolution of the sweetness receptor in primates. II. Gustatory responses of non-human primates to nine compounds known to be sweet in man.

The gustatory responses of nine compounds, namely glycine, D-phenylalanine, D-tryptophan, cyanosuosan, magapame, sucrononate, campame, cyclamate and superaspartame, all known as sweet in man, were studied in 41 species or subspecies of non-human primates, selected among Prosimii (Lemuridae and Lorisidae), Platyrrhini (Callitrichidae and Cebidae) and Catarrhini (Cercopithecidae, Hylobatidae and Pongidae). The first six compounds are generally sweet to all primates, which implies that they interact with the primate sweetness receptors essentially through constant recognition sites. Campame is sweet only to Cebidae and Catarrhini, cyclamate only to Catarrhini, superaspartame principally to Callitrichidae and Catarrhini, which implies that all these compounds interact with the receptors partly through variable recognition sites.

Evolution of the sweetness receptor in primates. I. Why does alitame taste sweet in all prosimians and simians, and aspartame only in Old World simians?

In the order Primates the responses to sucrose, alitame and aspartame were ascertained. All primates tested to date like sucrose and prefer this sweet substance to tap water. The artificial dipeptide aspartame was found to be not sweet in Prosimii and Platyrrhini (New World monkeys).

[Rapid and automatic acquisition and transmission of acid-base equilibrium parameters in a clinical biology laboratory (author's transl)].

The "pH-blood gas" department of our clinical biology laboratory was organized to meet rapidly and in the most reliable conditions possible the numerous and urgent analytical demands that had been confronting us. The structure was set up, therefore, in order to accelerate the speed at which blood samples could be transferred and make it possible to quickly and reliably obtain and transmit the results of the analyses. These necessities were satisfied thanks to the installation of a pneumatic tube allowing the rapid transfer of syringes, the utilization of automatic analysers, and the installation of a data processing system.

Correlation of chemical structure and taste in the cyclamate series and the steric nature of the chemoreceptor site.

The requirements of compounds in the cyclamate series for sweet taste stimulation are: synclinal conformation between NH and SO in the aminosulphonate group, length less than 0.7 nm of the group on the nitrogen, and hydrophobic character of the latter group. A hypothetical receptor site for these compounds should have a spatial barrier at a distance of about 0.