SALT PREFERENCE IN RATS: INFLUENCE OF AGE AND STRAIN

该项目的长期目标是确定哪些因素 导致人们对盐的偏好和摄入量不同。食盐 偏爱是指摄入钠或氯化钠。 (氯化钠)在没有生理需要的情况下，特别是 之所以感兴趣，是因为高盐分摄入量与 人类原发性高血压的发展和维持。 我们实验室以前的工作已经定义了以下情况 老鼠的行为明显偏离了“物种典型标准” 对盐的偏爱。已经检查了两个大鼠模型，盐 偏好大大偏离了这一常态。一只--幼鼠-- -可以被描述为盐暴食症，因为它不能避免 浓度高达4%和6%的高渗氯化钠溶液， 成年大鼠完全可以避免这种情况。另一个--一个 被称为Fischer-344的近交系大鼠表现出一种不同寻常的 对氯化钠溶液的厌恶。成年Fischer-344大鼠更喜欢 甚至是等渗或低渗的氯化钠溶液。这些 在盐偏好的连续体上，行为处于极端状态。 尽管可能涉及许多因素，但重点是 这一建议是一种假设，即年龄和应变差异在 阿米洛利敏感的钠转运在试验芽中起作用 这些大鼠对氯化钠的偏好差异很大。 短期和长期测试中味觉偏好的行为学研究 将被用来描述由 Fischer-344大鼠，并观察其个体发育。进食者 10日龄Long Evans大鼠对盐的行为 也要接受检查。行为和电生理方法 将被用来评估应变和年龄的假设 阿米洛利敏感钠转运机制的差异 味蕾参与了对盐表现出的厌恶 Fischer-344大鼠在避免高渗中的出现 乳汁中氯化钠溶液的行为学研究 阿米洛利敏感性递送阿米洛利和测量舔 在用粘度计进行的简短接触试验中对氯化钠溶液的行为， 电生理学研究检测细胞的多单位活动 水或阿米洛利后鼓索神经对氯化钠溶液的敏感性 前处理。

The long range goal of this project is to identify factors which contribute to variations in salt preference and intake. Salt preference refers to the ingestion of sodium or sodium chloride (NaCl) in the absence of physiological need and is of particular Interest because high salt Intake has been Implicated In the development and maintenance of essential hypertension in humans. Previous work in our laboratory has defined situations in which rats show significant departures from the "species typical norm" of salt preference. Two rat models have been examined where salt preference deviates sharply from this norm. One --the Infant rat- - could be characterized as a salt glutton, since it does not avoid hypertonic NaCl solutions at concentrations as high as 4% and 6%, which would be totally avoided by adult rats. The other --an inbred strain known as the Fischer-344 rat-- displays an unusual distaste for NaCl solutions. Adult Fischer-344 rats fall to prefer even isotonic or hypotonic NaCl solutions to water. These behaviors are at the extremes on a continuum of salt preference. Although a number of factors are likely to be involved, a focus of this proposal is the hypothesis that age and strain differences in amiloride-sensitive sodium transport at the tests bud contribute to the wide variations in NaCl preference displayed by these rats. Behavioral studies of taste preference in short and long term tests will be utilized to characterize the salt aversion displayed by Fischer-344 rats as well as examine its ontogeny. The ingestive behavior displayed by 10-day-old Long Evans rats toward salts will also be examined. Behavioral and electrophysiological approaches will be utilized to assess the hypothesis that strain and age differences in amiloride-sensitive sodium transport mechanisms at the taste bud are involved both in the aversion to salt displayed by Fischer-344 rats and in the emergence of avoidance of hypertonic NaCl solutions during the suckling period Behavioral studies of amiloride sensitivity delivery amiloride and measure licking behavior to NaCl solutions in brief access tests with a lickometer, electrophysiological studies examine multiunit activity of the chorda tympani nerve to NaCl solutions after water or amiloride pretreatment.