McBride W J, Freeman A R, Graham L T, Aprison M H
J Neurobiol. 1975 May;6(3):321-8. doi: 10.1002/neu.480060308.
The contents of alanine, proline, glycine, GABA, glutamate, and aspartate were measured in four bundles of axons (designated areas A through D) from the circumesophageal connective of the lobster (Homarus americanus). The contents of these amino acids were also determined in individual axons within specific bundles and in the external sheath covering the circumesophageal connective. Within the nerve bundles the levels of aspartate were highest of the amino acids measured, ranging from 1.95 +/- 0.12 mumol/mg protein in area C to 7.55 +/- 0.54 mumol/mg protein in area B. On the other hand, GABA had the lowest value in the four bundles; its highest level was found in area C (0.083 +/- 0.006 mu mol/mg protein) and the lowest in area B (none detected). The content of glycine ranged from 1.63 +/- 0.14 (area C) to 2.52 +/- 0.32 mumol/mg protein in area A; that for glutamate ranged from 0.390 +/- 0.019 (area C) to 1.01 +/- 1.03 (area B). The contents of alanine and proline changed relatively little from bundle-to-bundle. The content of aspartate was the highest of any of the amino acids assayed in individual axons (with diameters in the range of 40 to 65 mu) dissected from areas B and C. Glycine had the next highest content followed in order by glutamate, proline, and alanine. GABA was not detected in these axons. With the exception of GABA (which could not be detected), aspartate had the lowest level (0.066 +/- 0.017) and glycine had the highest level (2.00 +/- 0.498 mumol/mg protein) in the external sheath covering the the circumesophageal connective.
在龙虾（美洲螯龙虾）食管周围结缔组织的四束轴突（标记为A至D区域）中，测定了丙氨酸、脯氨酸、甘氨酸、γ-氨基丁酸（GABA）、谷氨酸和天冬氨酸的含量。这些氨基酸的含量也在特定束内的单个轴突以及覆盖食管周围结缔组织的外部鞘中进行了测定。在神经束内，所测氨基酸中天冬氨酸的含量最高，范围从C区域的1.95±0.12 μmol/mg蛋白质到B区域的7.55±0.54 μmol/mg蛋白质。另一方面，GABA在这四束中的含量最低；其最高水平出现在C区域（0.083±0.006 μmol/mg蛋白质），B区域最低（未检测到）。甘氨酸的含量范围从C区域的1.63±0.14到A区域的2.52±0.32 μmol/mg蛋白质；谷氨酸的含量范围从C区域的0.390±0.019到B区域的1.01±1.03。丙氨酸和脯氨酸的含量在不同束之间变化相对较小。在从B区域和C区域分离出的单个轴突（直径在40至65μm范围内）中，所测的任何氨基酸中天冬氨酸的含量最高。甘氨酸的含量次之，依次为谷氨酸、脯氨酸和丙氨酸。在这些轴突中未检测到GABA。除了GABA（无法检测到）外，在覆盖食管周围结缔组织的外部鞘中，天冬氨酸的含量最低（0.066±0.017），甘氨酸的含量最高（2.00±0.498 μmol/mg蛋白质）。
