Sclafani A
Department of Psychology, Brooklyn College, The City University of New York, Brooklyn 11210.
Brain Res Bull. 1991 Sep-Oct;27(3-4):383-6. doi: 10.1016/0361-9230(91)90129-8.
Rats are strongly attracted to the sweet taste of sugar. Recent behavioral studies demonstrate that rats also have a well-developed taste for starch-derived polysaccharides (e.g., Polycose). In fact, rats prefer Polycose to sucrose and other sugars at low concentrations. Polycose appetite develops at a very young age (9 days) and, thus, appears to be innate. The results of conditioned taste aversion tests suggest that rats taste Polycose as qualitatively different from sucrose. Recent electrophysiological findings support the idea that rodents have separate taste channels for polysaccharides and sugars. In particular, copper chloride suppresses the chorda tympani nerve response to sucrose and other sugars but has minimal effect on the neural response to Polycose. Also, Polycose evokes a profile of neural activity in the nucleus tractus solitarius that differs substantially from that produced by sucrose. Preliminary results indicate that polysaccharide and sugar tastes also differ in their metabolic consequences, i.e., unlike sugars, Polycose does not elicit a cephalic phase insulin response. The presumed function of polysaccharide taste is to facilitate the identification of starch-rich foods. Recent findings demonstrate that rats can readily detect starch even at low concentrations, but whether polysaccharide taste receptors or other orosensory receptors mediate this response remains to be clarified.
大鼠对糖的甜味有强烈的吸引力。最近的行为研究表明，大鼠对淀粉衍生的多糖（如聚葡萄糖）也有良好的味觉。事实上，在低浓度下，大鼠更喜欢聚葡萄糖而不是蔗糖和其他糖类。聚葡萄糖的食欲在非常年幼的时候（9天）就会出现，因此似乎是天生的。条件性味觉厌恶测试的结果表明，大鼠品尝聚葡萄糖时感觉其在性质上与蔗糖不同。最近的电生理研究结果支持这样一种观点，即啮齿动物对多糖和糖类有不同的味觉通道。特别是，氯化铜会抑制鼓索神经对蔗糖和其他糖类的反应，但对聚葡萄糖的神经反应影响最小。此外，聚葡萄糖在孤束核中引发的神经活动模式与蔗糖产生的模式有很大不同。初步结果表明，多糖和糖类的味觉在代谢结果上也有所不同，即与糖类不同，聚葡萄糖不会引发头期胰岛素反应。多糖味觉的推测功能是便于识别富含淀粉的食物。最近的研究结果表明，大鼠即使在低浓度下也能轻易检测到淀粉，但多糖味觉受体或其他口腔感觉受体是否介导这种反应仍有待阐明。
