Chemosensory Perception Laboratory, Department of Surgery (Otolaryngology), 9500 Gilman Drive-Mail Code 0957, University of California, San Diego, La Jolla, CA 92093-0957, USA.
Chem Senses. 2010 May;35(4):289-99. doi: 10.1093/chemse/bjq018. Epub 2010 Feb 26.
We have measured concentration detection (i.e., psychometric) functions to determine the odor detectability of homologous aliphatic aldehydes (propanal, butanal, hexanal, octanal, and nonanal) and helional. Subjects (16 < or = n < or = 18) used a 3-alternative forced-choice procedure against carbon-filtered air (blanks), under an ascending concentration approach. Generation, delivery, and control of each vapor were achieved via an 8-station vapor delivery device. Gas chromatography served to quantify the concentrations presented. Group and individual functions were modeled by a sigmoid (logistic) equation. Odor detection thresholds (ODTs) were defined as the concentration producing a detectability (P) halfway (P = 0.5) between chance (P = 0.0) and perfect detection (P = 1.0). ODTs decreased with carbon chain length: 2.0, 0.46, 0.33, and 0.17 ppb, respectively, from propanal to octanal, but the threshold increased for nonanal (0.53 ppb), revealing maximum sensitivity for the 8-carbon member. The strong olfactory receptor (OR) ligands octanal and helional (0.14 ppb) showed the lowest thresholds. ODTs fell at the lower end of previously reported values. Interindividual variability (ODT ratios) amounted to a factor ranging from 10 to 50, lower than typically reported, and was highest for octanal and hexanal. The behavioral dose-response functions emerge at concentrations 2-5 orders of magnitude lower than those required for functions tracing the activation of specific human ORs by the same aldehydes in cell/molecular studies, after all functions were expressed as vapor concentrations.
我们已经测量了浓度检测（即心理测量）功能，以确定同源脂肪醛（丙醛、丁醛、己醛、辛醛和壬醛）和乙位紫罗兰酮的气味可检测性。受试者（16≤n≤18）使用 3 种替代的强制选择程序，在上升浓度的方法下，对抗经过碳过滤的空气（空白）。每种蒸气的产生、输送和控制都是通过 8 个站的蒸气输送装置实现的。气相色谱法用于定量呈现的浓度。群体和个体功能由一个 S 形（逻辑）方程建模。气味检测阈值（ODT）定义为产生可检测性（P）的浓度，该可检测性（P）在机会（P=0.0）和完美检测（P=1.0）之间的一半（P=0.5）。ODT 随着碳链长度的增加而降低：从丙醛到辛醛，分别为 2.0、0.46、0.33 和 0.17 ppb，但壬醛的阈值增加（0.53 ppb），表明 8 个碳成员的敏感性最大。强嗅觉受体（OR）配体辛醛和乙位紫罗兰酮（0.14 ppb）的阈值最低。ODT 落在以前报道的数值的较低端。个体间的可变性（ODT 比值）达到 10 到 50 倍的范围，低于通常报道的值，对于辛醛和己醛，个体间的可变性最大。在所有功能都表示为蒸气浓度后，行为剂量-反应函数出现在比通过相同醛在细胞/分子研究中激活特定人类 OR 所需的浓度低 2-5 个数量级的浓度下。
