Pittman David W, Contreras Robert J
Department of Psychology, The Florida State University, Tallahassee, FL 32306-1270, USA.
Physiol Behav. 2002 Nov;77(2-3):277-89. doi: 10.1016/s0031-9384(02)00852-1.
Two experiments were conducted to determine the influence of dietary NaCl level on the integrated responses of the chorda tympani (CT) nerve to salt stimulation alone and mixed with the sodium-channel blocker, amiloride hydrochloride. Five groups of adult male rats were reared on regular chow containing either basal 0.1%, intermediate 1.0%, or high 3.0% NaCl from conception to postnatal day (PD) 30 or from conception to adulthood. Adult rats reared from conception to adulthood on basal dietary NaCl demonstrated a reduction in the CT nerve response to NaCl due to a decrease in the amiloride sensitive transduction mechanism. However, the CT nerve responses of adult rats reared on basal dietary NaCl to PD30 and then switched to intermediate dietary NaCl were similar to those of rats reared for a lifetime on intermediate dietary NaCl. Similarly, the CT nerve responses to NaCl in animals reared on high dietary NaCl from conception to PD30 and then switched to an intermediate NaCl diet were comparable to animals reared on intermediate and basal dietary NaCl. However, we found that exposure to high dietary NaCl led to a greater amiloride inhibition of NaCl responses. Thus, there is critical association between dietary NaCl level over two different exposure periods and CT nerve responsiveness to NaCl specifically regarding the degree of amiloride inhibition.
进行了两项实验，以确定日粮氯化钠水平对鼓索神经（CT）单独对盐刺激以及与钠通道阻滞剂盐酸阿米洛利混合刺激的综合反应的影响。将五组成年雄性大鼠从受孕饲养至出生后第30天（PD30）或从受孕饲养至成年，分别给予含基础氯化钠水平0.1%、中等水平1.0%或高水平3.0%的常规饲料。从受孕饲养至成年期的基础日粮氯化钠水平的成年大鼠，由于阿米洛利敏感转导机制的降低，其CT神经对氯化钠的反应有所减弱。然而，从受孕饲养至PD30且之后转换为中等日粮氯化钠水平的成年大鼠的CT神经反应，与终生饲养于中等日粮氯化钠水平的大鼠相似。同样，从受孕饲养至PD30且之后转换为中等氯化钠日粮的高日粮氯化钠水平饲养的动物对氯化钠的CT神经反应，与中等和基础日粮氯化钠水平饲养的动物相当。然而，我们发现，暴露于高日粮氯化钠水平会导致阿米洛利对氯化钠反应的抑制作用更强。因此，在两个不同暴露期的日粮氯化钠水平与CT神经对氯化钠的反应性之间存在关键关联，特别是在阿米洛利抑制程度方面。
