A PHYSICOCHEMICAL INVESTIGATION OF TASTE

该提案涉及味觉和味觉中的转导机制， 嗅觉 在味道的情况下，提出了两种方法。 一是 使用大鼠的体内方法，可以监测 整合鼓索反应和跨上皮电位，或 短路电流 脉冲电流或电压还允许 电导的连续记录。 第二种方法利用 离体舌上皮。 这种方法允许调查 各种药物对离子转运的影响 舌上皮的特性。 现在有证据表明，一种类型 钠盐味觉受体是一条钠转运途径， 味蕾细胞的膜 也有很好的证据表明， 在味觉上皮中也发现了转运途径。 因此 在舌上皮的一部分上平均的短路电流是 可能是味蕾细胞电流密度的一个很好的指示器。 通过记录跨上皮电位的时间过程， 短路电流和神经反应，组织 电生理学反应可以与那些在 味觉神经 初步数据表明，神经系统的发病 活动与电流的向内运动一致， 自适应与短路中的慢分量或第二分量一致 电流 药理学探针，如阿米洛利，将用于观察 如果神经抑制与短路抑制同时发生 电流 体外方法将允许研究两性离子， 抑制盐诱发的内向电流和西吡氯铵， 最近发现的舌跨上皮电流的增强剂。 的 牛蛙嗅粘膜体外制备方法的研究 有望产生信息的嗅觉分泌机制和 气味刺激的内向电流的离子基础。 当 纤毛侧受到气味刺激，反应是快速向内 电流瞬变之后是较慢的第二向内电流。 第一 成分可能是受体细胞来源。 结果应 在早期阶段确定当前运营商的身份 嗅觉传导

The proposal deals with the mechanism of transduction in both taste and olfaction. In the case of taste, two methods are proposed. The first is an in vivo method using the rat which allows the monitoring of the integrated chorda tympani response and the transepithelial potential or short-circuit current. Pulsed current or voltage also allows for a continuous record of the conductance. The second method utilizes the isolated lingual epithelium in vitro. This method allows the investigation of the effect of various pharmacological agents on the ion transport properties of the lingual epithelium. There is now evidence that one type of sodium taste receptor is a sodium transport pathway in the apical membranes of taste-bud cells. There is also good evidence that the apical transport pathway is also found in nongustatory epithelia. Thus, the short-circuit current averaged over a section of lingual epithelium is probably a good indicator of the current density across taste-bud cells. By recording the time course of the transepithelial potential or short-circuit current and the neural response, the tissue electrophysiological responses can be correlated with those seen in the gustatory nerves. Preliminary data indicate that the onset of neural activity coincides with the inward movement of current and that neural adaptation coincides with the slow or second component in the short-circuit current. Pharmacological probes, such as, amiloride, will be used to see if neural inhibition coincides with inhibition of the short-circuit current. The in vitro method will permit the study of zwitterions which inhibit the salt-evoked inward current and cetylpyridinium chloride, a recently discovered enhancer of the lingual transepithelial current. The development of an in vitro preparation of bullfrog olfactory mucosa promises to yield information on both olfactory secretory mechanisms and on the ionic basis of the odorant-stimulated inward current. When the ciliated side is stimulated with odorants, the response is a rapid inward current transient followed by a slower second inward current. The first component is probably of receptor cell origin. The results should establish the identity of the current carriers during the early phases of olfactory transduction.