El-Sharaby A, Ueda K, Wakisaka S
Department of Oral Anatomy and Developmental Biology, Osaka University Graduate School of Dentistry, Suita, Japan.
Arch Histol Cytol. 2001 Oct;64(4):401-9. doi: 10.1679/aohc.64.401.
We used alpha-gustducin, a taste-cell-specific G protein to investigate the onset of taste transduction and its relation to the development of the palatal and lingual taste buds. Frozen cryostat and paraffin sections were prepared from the palatal and lingual gustatory epithelium of the rat from birth till postnatal day 21 (PN 21d). At PN 1-7d, alpha-gustducin-immunoreactive solitary ovoid or bipolar cells were scattered among the oral epithelium either horizontally along the oral surface or vertically oriented between the basal lamina and oral surface. In the circumvallate and foliate papillae, these cells became wrapped in alpha-gustducin-immunonegative cells surrounded by an extracellular space forming a bud-like structure. Simultaneously, different stages of typical taste buds were recognized, but alpha-gustducin was only expressed in some neonatally developed pored buds. At PN 1d, alpha-gustducin was expressed in pored taste buds with a relatively higher frequency recorded in the soft palate as compared with the nasoincisor, circumvallate, and foliate papillae. The immunoreactive cells were spindle shaped with elongated processes extending from the base to the pore of the taste buds. During the second week, the solitary cells could no longer be recognized while the total counts of immunoreactive cells within the taste buds gradually increased. We argue that taste transduction is essentially required from the time of birth and can be fulfilled by both of the solitary chemosensory cells, which are immunoreactive for alpha-gustducin and scattered in the oral epithelium, and the taste cells within the mature taste buds. Moreover, the onset of taste transduction accomplished by the palatal taste buds developed earlier than that achieved by taste buds in the circumvallate and foliate papillae.
我们使用α-味导素（一种味觉细胞特异性G蛋白）来研究味觉转导的起始及其与腭部和舌部味蕾发育的关系。从出生至出生后第21天（PN 21d）的大鼠腭部和舌部味觉上皮制备冷冻切片机切片和石蜡切片。在PN 1 - 7d时，α-味导素免疫反应性的单个卵圆形或双极细胞沿口腔表面水平或在基底层和口腔表面之间垂直排列，散布在口腔上皮中。在轮廓乳头和叶状乳头中，这些细胞被α-味导素免疫阴性细胞包裹，周围有细胞外间隙，形成芽状结构。同时，识别出了典型味蕾的不同阶段，但α-味导素仅在一些新生发育的有孔味蕾中表达。在PN 1d时，α-味导素在有孔味蕾中表达，与鼻切牙、轮廓乳头和叶状乳头相比，软腭中记录到的频率相对较高。免疫反应性细胞呈纺锤形，有从基部延伸至味蕾孔的细长突起。在第二周，单个细胞不再被识别，而味蕾内免疫反应性细胞的总数逐渐增加。我们认为，味觉转导从出生时就基本需要，并且可以由对α-味导素免疫反应且散布在口腔上皮中的单个化学感觉细胞以及成熟味蕾内的味觉细胞来完成。此外，腭部味蕾完成的味觉转导起始比轮廓乳头和叶状乳头中的味蕾更早。
