A PHYSICOCHEMICAL INVESTIGATION OF TASTE

该提案涉及哺乳动物味觉的转导机制。 接待处。一种新的检测味觉效果的方法 引入了单元级。该方法允许应用品尝者 到味蕾的正常味觉敏感区，同时在同一 记录细胞电反应的时间。录音是使用 膜片钳技术。有了这些方法，就可以将 我们将检查大鼠舌头前部的细胞。单人 大鼠鼓索的纤维分析表明细胞的存在 这将在细胞顶端具有高度选择性的钠离子电导 薄膜。也应该有更少的选择性细胞对不同的 盐和酸。我们将制作一份细胞类型目录来测试这一点 假设。细胞内电势变化的动力学将是 在正常化学刺激条件下进行研究。可能的 将注意到动作电位的存在和细胞的动力学 将对适应进行研究。初步数据显示，心尖部 一些味觉细胞的膜具有阿米洛利阻断电导。这个 这些对阿米洛利敏感的根尖膜电导的离子特异性 将会被检查。CAMP可能与甜味有关 将探索转导。这将在单细胞级别上完成， 还使用了活体大鼠模型，在该模型中，鼓索对 蔗糖将通过跨上皮电位的变化或 电流欠压钳位。初步数据表明，一个基底侧向 在蔗糖的刺激下，膜电导被阻断。这个 阿米洛利阻滞钠的表达调控问题 导体将是地址。在缺钠大鼠中，有 可以通过钠调节来实现调节的证据 荷尔蒙。我们将从电生理学角度探讨这种可能性。 细胞水平和活体大鼠模型。心钠素， 通过cGMP发挥作用，是可能的调节物质之一。品味是一种 决定食物摄入量的主要因素。条件和物质 调节其表达将在以下领域产生强烈影响 钠敏感型高血压和肥胖等喂养障碍。

The proposal deals with the mechanism of transduction in mammalian taste reception. A new method for detecting the effects of tastants at the single cell level is introduced. The method permits tastants to be applied to the normal taste-sensitive regions of the taste-bud while at the same time recording the cell electrical response. Recordings are made using patch-clamp technology. With these methods the characteristics of the cells in the anterior part of the rat tongue will be examined. Single fiber analysis of the rat chorda tympani suggests the existence of cells that will have a highly selective sodium ion conductance in the cell apical membrane. There should also be less selective cells reactive to various salts and acids. A catalog of cell types will be made to test this hypothesis. The kinetics of the changing intracellular potential will be studied under conditions of normal chemical stimulation. The possible presence of action potentials will be noted and the kinetics of cellular adaptation will be studied. Preliminary data show that the apical membranes of some taste cells have amiloride-blockade conductances. The ion specificity of these amiloride-sensitive apical membrane conductances will be examined. The possible involvement of cAMP in the sweet taste transduction will be explored. This will be done on the single cell level, and also using a live-rat model in which the chorda tympani response to sucrose will be measured with changes in the transepithelial potential or current under voltage clamp. Preliminary data indicate that a basolateral membrane conductance is blocked during stimulation by sucrose. The question of the regulation of the expression of amiloride-blockade sodium conductances will be addresses. Among sodium-deprived rats there is evidence that regulation may be effected through sodium-regulating hormones. We shall explore this possibility electrophysiologically at the cellular level and with a live-rat model. Atrial natriuretic factor, acting via cGMP, is one of the possible regulatory substances. Taste is a major factor in determining food intake. The conditions and substances that modulate its expression will have a strong impact in the areas of sodium-sensitive hypertension and feeding disorders such as obesity.