Politis M J, Miller J E
Department of Medical Anatomy, University of Saskatchewan, Saskatoon, Canada.
Exp Neurol. 1988 May;100(2):297-304. doi: 10.1016/0014-4886(88)90109-4.
Dibutylcyclic AMP (DiBucAMP) can induce astroblast-containing cultures to form cells which resemble reactive astrocytes observed in vivo. In the present study, myelin- or axolemmal-enriched fractions were assessed for the ability to inhibit (DiBucAMP)-stimulated reactive-like changes in astrocytic cultures. Addition of exogenous myelin- or axolemmal-enriched fractions to DiBcAMP-exposed cultures prevented drug-induced elevation of lactic dehydrogenase (LDH) 2 days after initial addition of the drug and moderated DiBucAMP-induced decreases in the enzyme's activity normally observed 5 days later. The proportion of reactive colonies (i.e., those in which more than 50% of cells are stellate-shape) was significantly lower in cultures exposed to the drug plus myelin or axolemma vs those exposed to DiBucAMP alone. The inhibitory factors in axolemmal fractions were heat sensitive (at 100 degrees C), whereas those in myelin were not. Both fractions were inactivated by trypsin. Whole brain homogenates had no effect on diBucAMP-stimulated changes in culture.
二丁酰环磷腺苷（DiBucAMP）可诱导含成纤维细胞的培养物形成类似于体内观察到的反应性星形胶质细胞的细胞。在本研究中，评估了富含髓磷脂或轴膜的组分抑制（DiBucAMP）刺激的星形胶质细胞培养物中反应样变化的能力。在最初添加药物2天后，向暴露于DiBcAMP的培养物中添加外源性富含髓磷脂或轴膜的组分，可防止药物诱导的乳酸脱氢酶（LDH）升高，并缓解通常在5天后观察到的DiBucAMP诱导的该酶活性降低。与仅暴露于DiBucAMP的培养物相比，暴露于药物加髓磷脂或轴膜的培养物中反应性集落的比例（即其中超过50%的细胞为星状的集落）显著降低。轴膜组分中的抑制因子对热敏感（在100℃），而髓磷脂中的抑制因子则不敏感。两种组分都可被胰蛋白酶灭活。全脑匀浆对DiBucAMP刺激的培养物变化没有影响。
