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３－Ｇｌｕ示踪实验表明，谷氨酸可以透过胎盘屏障进入胎鼠体内，较均一地分布于中枢神经系统及内脏各器官。给母鼠隔日注射高、低剂量的谷氨酸单钠（ＭＳＧ，２．５ｍｓ／ｇ，１．０ｍｇ／ｇ）至分娩，对成年后的仔鼠进行检测发现，高剂量组仔鼠记忆能力及Ｙ－迷宫空间分辨学习能力均严重受损，下丘脑弓状核及腹内侧核神经元被明显破坏，出现胞质肿胀、核固缩、神经元数目减少。孕期ＭＳＧ处理还可以使仔鼠下丘脑和海马３Ｈ－Ｇｌｕ受体－配体结合量显著变化。采用ＡＲ－ＣＭ－ＭＩＣ阳离子检测系统观察单个神经元内游离Ｃａ２＋浓度（［Ｃａ２＋］ｉ）的变化时还发现，ＭＳＧ可以通过诱发胞外Ｃａ２＋内流及胞内钙库释放Ｃａ２＋来增高［Ｃａ２＋］ｉ。以上结果提示：ＭＳＧ对仔鼠的剂量依赖性神经毒性作用可能与其过度激活膜谷氨酸受体，引起细胞内Ｃａ２＋超载，最终导致特定脑区的神经元发生溃变甚至死亡有关，而这些变化可能正是仔鼠成年后学习记忆受损的原因。
3-Glu tracer experiments showed that glutamate can penetrate the placental barrier into the fetal rat body, more evenly distributed in the central nervous system and organs of various organs. High and low doses of monosodium glutamate (MSG, 2.5 mg / g, 1.0 mg / g) were injected into maternal mice every other day until delivery. The adult pups were examined and found that the memory ability And Y-maze spatial resolution of learning ability are severely damaged, hypothalamic arcuate nucleus and ventral medial neurons were significantly damaged, cytoplasm swelling, nuclear pyknosis, neuron number decreased. Pregnancy MSG treatment also significantly altered 3H-Glu receptor-ligand binding in the hypothalamus and hippocampus in offspring. Using AR-CM-MIC cation detection system to observe changes of intracellular free Ca2 + concentration ([Ca2 +] i) in single neurons, we also found that MSG can increase [Ca2 +] by inducing extracellular Ca2 + influx and intracellular Ca2 + release from Ca2 + i. The above results suggest that the dose-dependent neurotoxic effect of MSG on offspring rats may be related to its excessive activation of membrane glutamate receptors, causing overloading of intracellular Ca2 +, eventually leading to the degeneration and even death of neurons in specific brain regions. These changes Probably the pups adult learning and memory damage after the reason.