Adler R, Varon S
Brain Res. 1980 Apr 28;188(2):437-48. doi: 10.1016/0006-8993(80)90043-8.
Chick embryo ciliary ganglionic (CG) neurons will not survive in monolayer culture unless special supplements are provided in the medium. We have previously reported that two such supplements, chick embryo extract and medium conditioned over chick heart cell cultures (HCM) share the capacity to support survival of CG neurons but differ in their neurite-promoting effects. Thus, embryo extract elicited neuritic outgrowth only on collagen and HCM did so only on polyornithine (PORN), although both agents supported neuronal survival on both substrata. We report here the separation and quantitation of two different HCM components. One is a trophic agent which supports survival of CG neurons on either collagen or PORN, but does not seem to adsorb to either substratum. The other is a neurite-promoting factor (NPF) which adsorbs to PORN but not to collagen. Overnight incubation of HCM on PORN yields two products: (i) an NPF-deprived HCM, that has no neurite-promoting activity and (ii) an NPF-coated PORN, that promotes neuritic development of CG neurons trophically supported by either embryo extract or NPF-deprived HCM. CG requirements for neuritic outgrowth were also examined in explant cultures. No neurites were present after 24 h when explants were cultured in plain medium on PORN. Very extensive radial neuritic outgrowth was observed when explants were cultured in HCM on fresh PORN, or in NPF-deprived HCM on NPF-derivatized PORN. In contrast to what happens with dissociated cells, neuritic outgrowth was also present when ganglia were cultured in NPF-deprived HCM on fresh PORN. However, neurites grew radially only to a limited extent, after which they adopted a circular pattern grossly concentric to the ganglionic explant. It is proposed that explanted ciliary ganglia produce a neurite-promoting factor that coats the PORN substratum in widening circles.
鸡胚睫状神经节（CG）神经元在单层培养中无法存活，除非培养基中添加特殊的补充物。我们之前报道过，两种这样的补充物，即鸡胚提取物和鸡心脏细胞培养物（HCM）的条件培养基，都具有支持CG神经元存活的能力，但在促进神经突生长的作用方面有所不同。因此，胚胎提取物仅在胶原蛋白上能引起神经突生长，而HCM仅在聚鸟氨酸（PORN）上能引起神经突生长，尽管这两种物质都能支持神经元在两种基质上存活。我们在此报告两种不同HCM成分的分离和定量。一种是营养因子，它能支持CG神经元在胶原蛋白或PORN上存活，但似乎不吸附于任何一种基质。另一种是神经突促进因子（NPF），它吸附于PORN而不吸附于胶原蛋白。将HCM在PORN上过夜孵育会产生两种产物：（i）不含NPF的HCM，它没有神经突促进活性；（ii）涂有NPF的PORN，它能促进由胚胎提取物或不含NPF的HCM营养支持的CG神经元的神经突发育。还在外植体培养中研究了CG对神经突生长的需求。当外植体在PORN上的普通培养基中培养24小时后，没有神经突出现。当外植体在新鲜PORN上的HCM中培养，或在NPF衍生的PORN上的不含NPF的HCM中培养时，观察到非常广泛的放射状神经突生长。与解离细胞的情况不同，当神经节在新鲜PORN上的不含NPF的HCM中培养时，也会出现神经突生长。然而，神经突仅在有限程度上呈放射状生长，之后它们呈现出与神经节外植体大致同心的圆形模式。有人提出，移植的睫状神经节会产生一种神经突促进因子，该因子以逐渐扩大的圆圈覆盖PORN基质。
