Ghiaroni Valeria, Fieni Francesca, Pietra Pierangelo, Bigiani Albertino
Dipartimento di Scienze Biomediche, Sezione di Fisiologia, Università di Modena e Reggio Emilia, 41100 Modena, Italy.
Chem Senses. 2003 Nov;28(9):827-33. doi: 10.1093/chemse/bjg076.
Taste cells in adult mammals are functionally heterogeneous as to the expression of ion channels. How these adult phenotypes are established during postnatal development, however, is not yet clear. We have addressed this issue by studying voltage-gated K(+) and Cl(-) currents (I(K) and I(Cl), respectively) in developing taste cells of the mouse vallate papilla. I(K) and I(Cl) underlie action potential waveform and firing properties, and play an important role in taste transduction. By using the patch clamp technique, we analyzed these currents in a specific group of cells, called Na/OUT cells and thought to be sensory. In adult mice, three different electrophysiological phenotypes of Na/OUT cells could be detected: cells with I(K) (K cells); cells with both I(K) and I(Cl) (K+Cl cells); and cells with I(Cl) (Cl cells). In contrast, at early developmental stages (2-4 postnatal days, PD) there were no Cl cells, which appeared at PD 8. Our findings indicate a mechanism that contributes to building-up the functional heterogeneity of mammalian taste cells during the postnatal development.
成年哺乳动物的味觉细胞在离子通道表达方面功能各异。然而，这些成年表型在出生后发育过程中是如何形成的，目前尚不清楚。我们通过研究小鼠轮廓乳头发育中的味觉细胞的电压门控钾离子电流和氯离子电流（分别为I(K)和I(Cl)）来解决这个问题。I(K)和I(Cl)是动作电位波形和发放特性的基础，在味觉转导中起重要作用。通过使用膜片钳技术，我们在一组特定的细胞（称为Na/OUT细胞，被认为是感觉细胞）中分析了这些电流。在成年小鼠中，可以检测到Na/OUT细胞的三种不同电生理表型：有I(K)的细胞（K细胞）；既有I(K)又有I(Cl)的细胞（K+Cl细胞）；以及有I(Cl)的细胞（Cl细胞）。相比之下，在发育早期（出生后2 - 4天，PD）没有Cl细胞，Cl细胞在PD 8出现。我们的研究结果表明了一种在出生后发育过程中有助于构建哺乳动物味觉细胞功能异质性的机制。
