胶质细胞源性神经营养因子对运动神经元病培养模型的保护作用

GDNF Protects Themotor Neuron in Laboratory Animal Brain and Spinal Cord Samples

目的利用运动神经元病的脑片和脊髓片培养模型,观察胶质细胞源性神经营养因子(GDNF)对运动神经元的保护作用。方法取1日龄SD乳鼠的大脑做脑片培养,取8日龄SD乳鼠脊髓做脊髓片培养。脑片在培养2周后,脊髓片在培养1周后,随机分为对照组、模型组(100μmol/LTHA)、不同浓度GDNF组(1ng/ml、5ng/ml和50ng/ml),继续培养3周后,SMI-32免疫组化染色,分别计数脑片中皮层运动神经元和脊髓片中前角运动神经元数目的变化,测定培养液中乳酸脱氢酶(LDH)的含量。结果模型组SMI-32阳性的皮层运动神经元数目和脊髓运动神经元数目较对照组明显减少,差异有显著性意义(P<0.05),而GDNF各组神经元存活数目较模型组显著增多,差异有显著性意义(P<0.05),脑片组和脊髓片组中的模型组LDH含量均对照组显著增高,差异有显著性意义(P<0.05),GDNF各组培养液中LDH含量较对照组均升高,差异有显著性意义(P<0.05)。结论GDNF能保护运动神经元免受谷氨酸兴奋毒性的损伤,使得GDNF在临床上治疗MND成为可能。

Objective Using the laboratory brain slice culture and spinal cord slice culture to investigate the protective effects of glial cell derived neurotrophic factor （GDNF） on injured motor neurons. Methods brain slice cultures were prepared using brain slices from 1 - day - old rat and the spinal cord slices were obtained from 8 - day - old rat . After 2 weeksculturefor the brain slices; and 1 week culture for spinal cord slices, the slices were divided into 5 groups： control group, THA model group （ 100 μmoL/L THA） and GDNF groups （ 1 ng/ml, 5 ng/ml and 50 ng/ml）. Three weeks＇later, we calculated the number of motor neurons using SMI -32 immunohistochemical staining. Lactate dehydrogenase （LDH） level in culture medium was also measured. Results SMI -32 positive cortical motor neurons and spinal motor neurons in the THA model group were significantly decreased compared with those in the control group. The motor neurons in GDNF groups were markedly higher comparing to the THA model group. LDH level in GNFD groups were significantly lower comparing to the control group. Conclusion GDNF protects motor neurons from the THA toxicity in laboratory, animal model.