The distribution and abundance of the calcium binding protein, calbindin D-28k (CB) immunoreactivity in the taste buds of the circumvallate papillae and larynx were compared between normoxic and chronically hypoxic rats (10% O2 for 8 weeks). In the normoxic rats, CB immunoreactivity was observed in some cells and fibers of the intragemmal region of the taste buds in the circumvallate papillae. ...

Gustatory neurons transmit chemical information from taste receptor cells, which reside in taste buds in the oral cavity, to the brain. As adult taste receptor cells are renewed at a constant rate, nerve fibers must reconnect with new taste receptor cells as they arise. Therefore, the maintenance of gustatory innervation to the taste bud is an active process. Understanding how this process is r...

Although it had long been believed that embryonic taste buds in vertebrates were induced to differentiate by ingrowing nerve fibers, we and others have recently shown that embryonic taste buds can develop normally in the complete absence of innervation. This leads to the question of which tissues, if any, induce the formation of taste buds in oropharyngeal endoderm. We proposed that taste buds,...

mice. In particular, these types of studies have been performed using animals that have disrupted gustatory University of Denver Denver, Colorado 80208 innervation due to the lack of a particular neurotrophin, brain-derived neurotrophic factor (BDNF), or its principal receptor, trkB. BDNF is expressed in developing taste For the past century, studies of the development of taste papillae (Nosrat...

The sensory organs for taste in chickens (Gallus sp.) are taste buds in the oral epithelium of the palate, base of the oral cavity, and posterior tongue. Although there is not a pan-taste cell marker that labels all chicken taste bud cells, α-Gustducin and Vimentin each label a subpopulation of taste bud cells. In the present study, we used both α-Gustducin and Vimentin to further characterize ...

The epithelium of the circumvallate papillae of rat tongues was stripped off by treatment with 0.005% elastase in a state when many taste buds were present. The taste buds were isolated from the stripped epithelium by further treatment with 0.005% elastase and 0.08% trypsin. A protein which was thought to be characteristic of taste buds was found from semimicro disc polyacrylamide gel electroph...

The G-protein subunit alpha-gustducin, which is similar to rod transducin, has been implicated in the transduction of both sweet- and bitter-tasting substances. In rodents, there are differences in sensitivity to sweet and bitter stimuli in different populations of taste buds. Rat fungiform taste buds are more responsive to salts than to sweet stimuli, whereas those on the palate respond predom...

The rat vallate papilla is bilaterally innervated by the IXth nerve whose axons are required for the normal development of its several hundred taste buds. Temporary denervation during the developmental sensitive period for taste buds prevented most vallate taste buds from forming. Specifically, removing one IXth nerve and crushing the other in 3 day old neonates eliminated axons from the vallat...

Taste buds are unusual in requiring ATP as a transmitter to activate sensory nerve fibers. In response to taste stimuli, taste cells release ATP, activating purinergic receptors containing the P2X2 and P2X3 subunits on taste nerves. In turn, the released ATP is hydrolyzed to ADP by a plasma membrane nucleoside triphosphate previously identified as nucleoside triphosphate diphosphohydrolase-2 (N...

The palatal region of the oral cavity in rodents houses 100-300 taste buds and is particularly sensitive to sweet and umami compounds; yet, few studies have examined the expression patterns of transduction-related molecules in this taste field. We investigated the interrelationships between members of the T1R family and between each T1R and gustducin in palatal taste buds. Similar to lingual ta...