Department of Physiology and Pathophysiology, Xi'an Jiaotong University School of Medicine, Ministry of Education, Xi'an, Shaanxi, PR China.
Brain Res Bull. 2012 Oct 1;89(1-2):8-15. doi: 10.1016/j.brainresbull.2012.06.013. Epub 2012 Jul 11.
Previous studies reported that NaCl intake was down-regulated in rats with bilateral lesions of the central nucleus of the amygdala (CeA). In line with the evidence from anatomical and physiological studies, such an inhibition could be the result of altered taste threshold for NaCl, one of the important factors in assessing taste functions. To assess the effect of CeA on the taste threshold for NaCl, a conditioned taste aversion (CTA) to a suprathreshold concentration of NaCl (0.1M) in rats with bilateral lesions of CeA or sham lesions was first established. And then, two-bottle choice tests between water and a series of concentrations of NaCl were conducted. The taste threshold for NaCl is defined as the lowest concentration at which there is a reliable difference scores between conditioned and control subjects. Rats with CeA lesions acquired a taste aversion for 0.1M NaCl when it was paired with LiCl and still retained the aversion after the two-bottle choice test. The results of the two-bottle choice test showed that the taste threshold for NaCl was 0.0006M in rats with CeA lesions, whereas in rats with sham lesions the threshold was 0.005M, which was identical to that of normal rats. The conditioned results confirm the claim that CeA is not essential in the profile of conditioned taste aversion. Our findings demonstrate that lesions of the CeA increased the sensitivity to NaCl taste in rats, indicating that the CeA may be involved in encoding the intensity of salty gustation elicited by NaCl.
先前的研究报道，双侧损毁杏仁中央核（CeA）的大鼠的 NaCl 摄入量减少。与解剖学和生理学研究的证据一致，这种抑制可能是 NaCl 味觉阈值改变的结果，而 NaCl 是评估味觉功能的重要因素之一。为了评估 CeA 对 NaCl 味觉阈值的影响，首先在双侧 CeA 损伤或假损伤大鼠中建立了对超阈值浓度 NaCl（0.1M）的条件性味觉厌恶（CTA）。然后，进行了 between water 和一系列 NaCl 浓度的双瓶选择测试。NaCl 的味觉阈值定义为条件和对照受试者之间存在可靠差异分数的最低浓度。当 0.1M NaCl 与 LiCl 配对时，CeA 损伤大鼠对其产生味觉厌恶，并且在双瓶选择测试后仍然保留厌恶。双瓶选择测试的结果表明，CeA 损伤大鼠的 NaCl 味觉阈值为 0.0006M，而假损伤大鼠的阈值为 0.005M，与正常大鼠相同。条件结果证实了 CeA 并非条件味觉厌恶特征所必需的说法。我们的研究结果表明，CeA 损伤增加了大鼠对 NaCl 味觉的敏感性，表明 CeA 可能参与编码由 NaCl 引起的咸味味觉的强度。
