ACTION OF MUSCLE TROPHIC FACTORS ON SPINAL MOTOR NEURONS

已经纯化了20，000道尔顿的阳离子多肽， 来自新生大鼠骨骼肌提取物的均一性。 的 将纯化的肽加入到解离的 胚胎大鼠脊髓神经元促进 胆碱乙酰转移酶和乙酰胆碱合成活性， 但不影响脊髓的整体代谢活动 cultures. 这种多肽代表了唯一的骨骼肌- 纯化至均一的衍生神经营养因子，此外， 神经生长因子，它是唯一的其他神经营养因子， CNS衍生神经元的胆碱能发育。 鸡的处理 胚胎在卵内与部分纯化的肽在 正常的细胞死亡期挽救了运动神经元， 会死的 因此，这种神经营养肽似乎是 对运动神经元的存活和发育很重要。 我们 目前的努力是针对进一步表征的 该因子对体外和体内发育的影响 运动神经元通过直接应用和通过发展 对纯化因子的特异性抗体。

A 20,000 dalton cationic polypeptide has been purified to homogeneity from extracts of neonatal rat skeletal muscle. The addition of the purified peptide to dissociated cultures of embryonic rat spinal cord neurons enhances the development of choline acetyltransferase and acetylcholine synthesis activities, but does not affect the overall metabolic activity of spinal cord cultures. This polypeptide represents the only skeletal muscle- derived neurotrophic factor purified to homogeneity, and besides NGF, it is the only other neurotrophic factor which affects cholinergic development of CNS-derived neurons. Treatment of chick embryos in ovo with the partially purified peptide during the normal cell death period rescues motor neurons which otherwise would have died. Thus, this neurotrophic peptide appears to be important for the survival and development of motor neurons. Our present efforts are directed at further characterization of the effects of this factor on the in vitro and in vivo development of motor neurons by direct application and through the development of specific antibodies to the purified factor.