Study of the transduction mechanisms in taste cell.

味觉产生的味觉感觉是一个化学-电信号转导过程，在味觉与受体细胞的特定相互作用下导致膜去极化。已经提出了几种解释味觉转导的机制，包括直接的味觉门控通透性变化，已经积累的令人信服的证据表明c-GMP， C-AMP和/或IP-在这一过程中充当细胞内信使。虽然味觉刺激c^3-GMP是介导味觉转导的一个有吸引力的方案。这种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的激活程度与甜味诱导的受体电位振幅呈正相关。由此得出结论，c-GMP活性是味觉转导的关键因素。此外，还提出了苦味引起IP_3浓度的增加。这些研究表明，每种味觉都可以激活味觉转导中的第二信使通路。然而，它们与味觉转导过程的关系尚不清楚。一个重要的标准候选的第二信使的味觉转导是它的形成必须伴随着味觉刺激的开始。为了探究被激活的第二信使系统的类型是否与味觉质量相关，我们对来自甜、苦、酸和盐的个体味觉进行了分析，以了解它们激活c-GMP或ip_3通路的潜力。放射免疫分析方法适用于了解细胞味觉转导特性，然而，在观察细胞内电位和单通道特性时，可能会错过这种转导。这是一个问题，是否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。一个重要的标准候选的第二信使的味觉转导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，对小鼠舌头味觉细胞的四种主要味觉品质激活第二信使通路的潜力进行了分析。研究发现，并不是每种味道都能激活同一种第二信使。蔗糖增加了c-GMP的浓度，奎宁增加了IP_3的浓度。少

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