Study of the transduction mechanisms in taste cell.

味觉产生的味觉是通过化学-电信号转导过程产生的，当味觉与受体细胞发生特定的相互作用时，该过程会导致膜去极化。已经提出了几种解释味觉转导的机制，包括直接味觉门控通透性的变化，已经积累的令人信服的证据表明，c-GMP、C-AMP和/或IP-1在这一过程中起着细胞内信使的作用。虽然味觉刺激c^3-GMP是一种有吸引力的味觉转导方案。这个机制是否负责检测所有的味道，或者是否涉及不同的第二信使途径，这是值得怀疑的。最近的电生理研究表明，C-GMP的激活幅度与甜味诱导的受体电位的幅度呈正相关。结果表明，c-GMP活性在味觉转导中起关键作用。The Furthe…此外，还提出了苦味引起IP_3浓度升高的观点。这些研究表明，每一种味道都可以激活味觉转导中的替代第二信使通路。然而，它们与味觉传导过程的关系尚不清楚。味觉转导的候选第二信使的一个重要标准是它的形成必须伴随着味觉刺激的开始。为了探讨被激活的第二信使系统的类型是否与味觉品质相关的问题，已对来自甜、苦、酸和盐的个体味觉进行了激活c-GMP或IP_3途径的潜力的分析。放射免疫分析方法适合于了解细胞的味觉转导特性，但当观察细胞内电位和单通道的特性时，这种转导可能被遗漏。这是一个问题，是一个转导机制负责检测所有的味道，或者是否涉及不同的第二信使途径。味觉转导的候选第二信使的一个重要标准是它的形成必须伴随着味觉刺激的开始。本研究利用放射免疫分析技术，在小鼠舌味细胞中对四种主要的味觉品质进行了激活第二信使通路的潜力分析。研究发现，每种味道并不都能激活相同的第二信使。蔗糖增加c-GMP的浓度，奎宁增加IP_3的浓度。

The sensation of taste caused by taste is producesd by a chemo-electrical signal transduction process, which upon specific interaction of taste with receptor cells leads to a membrane depolarization. Several mechanisms have been proposed to explain taste transduction, including direct taste gated permeability changes, compelling evidence has been accumulated suggesting that c-GMP, C-AMP and/or IP-, serves as an intracellular messenger in this process. Although the stimulation of c^3-GMP by taste is an attractive scheme for mediating taste transduction. It is questionable Whether this mechanien is responsible for detection of all tastes, or whether different second messenger pathways are involved. Recent electrophysiological study suggests that there is a positive correlation between the magnitudeof C-GMP activation and the amplitude of the receptor potential induced by sweet taste. From the result, it has been concluded that c-GMP activity is a key element in taste transduction. Furthe … More rmore it was also proposed that bitter taste caused an increase of IP_3 concentration. These studies demonstrated that each taste can activate alternative second messenger pathways in the taste transduction. However, their relation to the taste transduction process is unclear. One important criterion for a candidate second messenger of taste transduction is that its formation must accompany by the onset of the taste stimulus. In order to approach the question if the type of second messenger system that is activated can be correlated to taste qualities, individual tastes from sweet, bitter, sour and salt have been assayed for their potential to activate either the c-GMP or the IP_3-pathway- Radio-immuno assay methods are appropriate to understand cellular taste transduction properties whereas, such transduction may be missed when looking at properties of intracellular potentials and single channels.It is a question whether a transduction mechanism is responsible for detection of all tastes, or whether different second messenger pathways are involved. One important criterion for a candidate second messenger of taste transduction is that its formation must accompany by the onset of the taste stimulus. This study demonstrated that the primary four taste qualities were assayed for their potential to activate second messenger pathways using radioimmuno assay technique in taste cells from mouse tongue. It was found that each taste does not all activate the same second messenger. Sucrose increased the concentration of c-GMP and quinine increased the concentration of IP_3. Less