Myers Kevin P
Department of Psychology, Programs in Animal Behavior and Neuroscience, Bucknell University, USA.
Appetite. 2017 May 1;112:196-200. doi: 10.1016/j.appet.2017.01.013. Epub 2017 Jan 12.
Sensory-specific satiety (SSS) is the temporary decreased pleasantness of a recently eaten food, which inhibits further eating. Evidence is currently mixed whether SSS is weaker in obese people, and whether such difference precedes or follows from the obese state. Animal models allow testing whether diet-induced obesity causes SSS impairment. Female rats (n = 24) were randomly assigned to an obesogenic high-fat, high-sugar choice diet or chow-only control. Tests of SSS involved pre-feeding a single palatable, distinctively-flavored food (cheese- or cocoa-flavored) prior to free choice between both foods. Rats were tested for short-term SSS (2 h pre-feeding immediately followed by 2 h choice) and long-term SSS (3 day pre-feeding prior to choice on day 4). In both short- and long-term tests rats exhibited SSS by shifting preference towards the food not recently eaten. SSS was not impaired in obese rats. On the contrary, in the long-term tests they showed stronger SSS than controls. This demonstrates that neither the obese state nor a history of excess energy consumption fundamentally causes impaired SSS in rats. The putative impaired SSS in obese people may instead reflect a specific predisposition, properties of the obesogenic diet, or history of restrictive dieting and bingeing.
感官特异性饱腹感（SSS）是指最近食用的食物的愉悦感暂时降低，从而抑制进一步进食。目前关于肥胖人群的SSS是否较弱，以及这种差异是先于肥胖状态还是继发于肥胖状态，证据并不一致。动物模型可以用来测试饮食诱导的肥胖是否会导致SSS受损。将雌性大鼠（n = 24）随机分为致肥胖的高脂肪、高糖选择饮食组或仅喂食普通食物的对照组。SSS测试包括在自由选择两种食物之前，先喂食一种可口的、味道独特的食物（奶酪味或可可味）。对大鼠进行短期SSS测试（预喂食2小时后立即进行2小时的选择）和长期SSS测试（在第4天选择之前预喂食3天）。在短期和长期测试中，大鼠都通过将偏好转向最近未食用的食物来表现出SSS。肥胖大鼠的SSS并未受损。相反，在长期测试中，它们表现出比对照组更强的SSS。这表明肥胖状态和能量消耗过多的历史都不会从根本上导致大鼠的SSS受损。肥胖人群中假定的SSS受损可能反而反映了一种特定的易感性、致肥胖饮食的特性，或限制饮食和暴饮暴食的历史。
