Abstract:
In addition to its sweet taste, glucose has potent and rapid postoral actions (appetition) that enhance its reward value. This has been demonstrated by the experience-induced preference for glucose over initially preferred nonnutritive sweetener solutions in 24-h choice tests. However, some sweetener solutions (e.g., 0.8% sucralose) have inhibitory postoral actions that may exaggerate glucose appetition whereas others (e.g., 0.1% sucralose + 0.1% saccharin, S+S) do not. Experiment 1 revealed that food-restricted (FR) male C57BL/6J mice displayed similar rapid glucose appetition effects (stimulation of glucose licking within minutes) and conditioned flavor preferences following 1-h experience with flavored 0.8% sucralose or 0.1% S+S and 8% glucose solutions. Thus, the inhibitory effects of 0.8% sucralose observed in 24-h tests were not apparent in 1-h tests. Experiment 2 evaluated the effects of food deprivation state and sweetener concentration on glucose appetition in female mice. Unlike FR mice tested with 0.1% S+S and 8% glucose, ad libitum (AL) fed mice displayed no stimulation of 8% glucose licking in the 1-h tests. A second ad libitum group (AL) tested with 0.2% S+S and 16% glucose solutions displayed stimulation of 16% glucose licking by the third 1-h test. Both AL groups, like the FR group, developed a preference for the glucose-paired flavor over the S+S paired flavor. Thus, food restriction promotes increased glucose licking but is not required for a conditioned preference. The FR male mice (Exp. 1) and FR female mice (Exp. 2) showed similar appetition responses (licking stimulation and flavor preference) to 8% glucose.
摘要:
除了它的甜味,葡萄糖具有有效而快速的后作用(食欲),可增强其奖励价值。在24小时选择测试中,经验诱导的对葡萄糖的偏爱超过了最初首选的非营养性甜味剂溶液,证明了这一点。然而,一些甜味剂溶液(例如,0.8%三氯蔗糖)具有可能夸大葡萄糖食欲的抑制性作用,而其他(例如,0.1%三氯蔗糖+0.1%糖精,S+S)不。实验1显示,食物限制(FR)雄性C57BL/6J小鼠在使用0.8%三氯蔗糖或0.1%SS和8%葡萄糖溶液调味1小时后,表现出相似的快速葡萄糖食欲作用(在几分钟内刺激葡萄糖舔)和条件风味偏好。因此,在24小时试验中观察到的0.8%三氯蔗糖的抑制作用在1小时试验中不明显。实验2评估了食物剥夺状态和甜味剂浓度对雌性小鼠葡萄糖食欲的影响。与用0.1%S+S和8%葡萄糖测试的FR小鼠不同,在1小时的测试中,随意喂养(AL)的小鼠没有表现出8%葡萄糖舔的刺激。用0.2%S+S和16%葡萄糖溶液测试的第二个随意组(AL)通过第三个1-h测试显示16%葡萄糖舔的刺激。两个AL组,像FR组一样,开发了对葡萄糖配对风味的偏好,而不是SS配对风味。因此,食物限制会促进葡萄糖舔作用增加,但条件偏好则不需要。FR雄性小鼠(Exp。1)和FR雌性小鼠(Exp。2)对8%葡萄糖表现出相似的食欲反应(舔刺激和风味偏好)。