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Taste Receptor Cells (taste + receptor_cell)
Selected AbstractsStructural diversification of the gustatory organs during metamorphosis in the alpine newt Triturus alpestrisJOURNAL OF ANATOMY, Issue 3 2007Krystyna Abstract Gustatory organs of the taste bud type occur in the epithelial lining of the oropharyngeal cavity of alpine newt larvae. They resemble the taste buds of bony fish, both in appearance (as revealed by scanning electron microscopy) and in detailed internal structure (seen on transmission electron micropscopy). During metamorphosis, at stage 55 of development, the secondary tongue (i.e. the soft tongue) is well formed and the anlages of taste discs are clearly apparent. Somewhat later, taste discs also appear in the epithelial lining outside the tongue, paralleling the disappearance of the taste buds. Well-developed taste discs of the newt differ from taste buds mainly by their structurally diversified set of ,associate cells' (mucous, wing and glial cells), which have no synaptic contact with nerve fibres. These cells accompany the neurosensory cellular components of the taste disc, i.e. the taste receptor cells and basal cells. This indicates that gustatory organs in metamorphosed newts, regardless of their small dimensions, fulfil the criteria established for taste discs previously defined in other Caudata and Anura species. Therefore, in the development of the newt there are two subsequent types of gustatory organs and two generations of the tongue: primary, in the larvae, and secondary, in metamorphosed animals. [source] Group IIA phospholipase A2 is coexpressed with SNAP-25 in mature taste receptor cells of rat circumvallate papillaeTHE JOURNAL OF COMPARATIVE NEUROLOGY, Issue 6 2006Hideaki Oike Abstract The taste buds are composed of heterogeneous cell populations with diverse properties and at different stages of maturity. It is important to define the relationships between cell properties and cell maturity to understand the molecular events involved in intracellular taste signaling. In the present study, in situ hybridization analysis indicated that group IIA phospholipase A2 (PLA2 -IIA) is expressed in a subset of taste bud cells. Immunohistochemical studies showed that PLA2 -IIA was expressed in a subset of cells expressing phospholipase C,2, a molecule essential for taste signaling in taste receptor cells, and also that some PLA2 -IIA-positive cells expressed gustducin (Ggust), a bitter-taste-signaling molecule. Although PLA2 -IIA and Ggust were expressed at similar frequencies in taste buds, bromodeoxyuridine (BrdU) chase experiments indicated that the expression of Ggust began 2 days after BrdU injection, whereas the expression of PLA2 -IIA commenced after 4 days. In addition, PLA2 -IIA was coexpressed with SNAP-25, a synaptosomal-associated protein. These results indicated that PLA2 -IIA is expressed in mature taste receptor cells that possess exocytotic machinery. J. Comp. Neurol. 494:876,886, 2006. © 2005 Wiley-Liss, Inc. [source] | ||||||||||