【摘要】 咸和酸直接通过顶部非门控或化学门控离子通道转导。唾液中的苦味化合物激活T2R/TRB同型体，这种激活导致味导素异聚体的激活，被激活的α-味导素又激活PDE,PDE水解cAMP,cAMP水平的降低使环核苷酸抑制的阳离子通道去抑制，从而使细胞内Ca2+升高。从激活的味导素释放出来的Gβ,γ亚基二聚体激活PLC,产生IP3，从而产生Ca2+从内质网Ca2+库中释放出来。细胞内Ca2+的增加导致神经递质的释放。唾液中的L-谷氨酸和膜上的mGluR4结合，这种结合导致非特异性阳离子通道的关闭，导致细胞膜的超极化。

    【关键词】 味觉；感觉转导

    Progress in study of taste transduction

    XIAO Hui,CHANG Qing, ZHENG Chang-min,et al.

    Wanjie Medical College,Zibo,Shandong 255213，China

    【Abstract】 Salty and sour directly transduction by apical channels that are non-gated channel or chemically-gated channel. Bitter compounds in saliva activate particular T2R/TRB isoforms which activate gustducin heterotimers, activated α-gustducin stimulates PDE to hydrolyze cAMP, the decreased cAMP may disinhibit cyclic nucleotide-inhibited channels to elevate intracellular Ca2+. Gβ,γ subunits released from activated α-gustducin activate PLC to generate IP3 which lead to release of Ca2+ from internal stores. A rise in intracellular Ca2+ followed by neurotransmitter release. L-glutamate in saliva binds to membrane mGluR4 which leads to closure of unspecific cation channel causing hyperpolarization of cells membrane. ......