SALT TASTE TRANSDUCTION AND ITS HORMONAL REGULATION

拟议工作的最终目标是确定 参与真菌状和环状的盐的转导 味觉感受器细胞和盐转导元件的调节 肽激素精氨酸加压素和心房钠尿肽。 使用电生理学方法，我们将解决以下问题 具体目标： 1.咸味刺激的传导机制是什么？ 仓鼠的菌状和轮廓状味觉感受器细胞？钠盐 真菌状味觉受体细胞中的转导通过Na内流发生， 阿米洛利敏感的钠通道，但也有一个阿米洛利- 不太容易理解的不敏感成分。轮廓味觉 受体细胞也对钠盐有反应，但它们的转导机制 尚未确定。使用膜片钳记录和 上皮运输测量味觉组织，我们将确定 菌状和环状味觉感受器的基本电生理学 细胞我们还将确定离子钠运输途径，在这些 细胞，以阐明盐转导的机制。 2.血管加压素和心钠素对心肌梗死的影响 盐的传导元件我们最近的研究表明， 加压素增强真菌样味觉中阿米洛利敏感性钠电流 受体细胞加上初步证据表明， 心房钠尿肽减少跨上皮钠通量，表明， 外周钠盐转导可能是神经调节的。 我们将 表征加压素和心房肌的急性和慢性作用 利钠肽对跨上皮钠转运和钠转导的影响 在整个细胞和单通道水平的通道，特别是支付 注意阿米洛利敏感的钠通道。然后我们将决定 这些细胞反应的靶点和途径 两种荷尔蒙 总之，这些研究将阐明基本的电生理学 味觉感受器细胞的特性和钠盐转导机制 在仓鼠身上此外，它将首次审视 激素在外周味觉调节中的作用 响应能力。这些研究将增进对营养素的了解， 化学感受及其调节，以及提供一般的见解， 神经元如何处理感官刺激。

The ultimate goal of the proposed work is to determine the mechanisms involved in the transduction of salts in the fungiform and circumvallate taste receptors cells and the regulation of salt transducing elements by the peptide hormones arginine vasopressin and atrial natriuretic peptide. Using an electrophysiological approach, we will address the following specific aims: 1. What are the mechanisms for transduction of salty taste stimuli in the fungiform and circumvallate taste receptor cells of hamsters? Sodium salt transduction in fungiform taste receptor cells occurs by Na influx through amiloride-sensitive Na channels, but there is also an amiloride- insensitive component that is not well understood. Circumvallate taste receptor cells also respond to Na salts, but their transduction mechanisms have not been determined. Using a combination of patch clamp recording and epithelial transport measurements on taste tissue, we will determine the basic electrophysiology of fungiform and circumvallate taste receptor cells. We will also determine the ionic Na transport pathways in these cells in order to elucidate the mechanisms for salt transduction. 2. What are the effects of vasopressin and atrial natriuretic peptide upon the transducing elements for salts? Our recent work showing that vasopressin enhances amiloride-sensitive Na currents in fungiform taste receptor cells coupled with preliminary evidence which demonstrates that atrial natriuretic peptide reduces transepithelial Na flux, suggests that peripheral Na salt transduction may be hormonally regulated. We will characterize the acute and chronic effects of vasopressin and atrial natriuretic peptide upon transepithelial Na transport and Na transducing channels at the whole cell and single channel level, paying particular attention to the amiloride-sensitive Na channel. We will then determine the targets and the pathways involved in the cellular response to these two hormones. Overall, these studies will elucidate basic electrophysiological properties of taste receptor cells and mechanisms for Na salt transduction in the hamster. Additionally, it will, for the first time, look at the role of hormones in the regulation and modulation of peripheral gustatory responsiveness. These studies will enhance understanding of nutrient chemoreception and its regulation as well as provide general insights into how neurons transduce sensory stimuli.