マウス茸状乳頭味蕾細胞の巨視的構造と電位依存性電流

抄録

We investigated the macroscopic structure of 42 taste bud cells (TBCs) in mouse fungiform papillae by labeling them with a probe biocytin while recording voltage-gated currents under in-situ patch clamp conditions. TBCs were classified into three types by the number of their dendrites; round (no dendrites, 〜12% of labeled TBCs), rod (one dendrite, 〜55%), and branch types (more than one dendrites, 〜33%). No round cells, 〜40% of rod cells, and 〜20% of branch cells reach taste ducts. There were no significant differences in the magnitude of their voltage-gated currents, and their membrane conductance among these types. The length of their dendrites was negligibly shorter than their space constants. The present results suggest that the cell membrane of TBCs is practically at the same potential as far as membrane characteristics remain passive, and that both rod and branch cells consist of different microscopic cell types, type I-IV.