Pietsch P
School of Optometry, Indiana University, Bloomington 47405.
Cytobios. 1993;76(304):7-11.
During tail regeneration in the axolotl larva, Ambystoma mexicanum, retinoic acid reduced mitosis some 10-fold in the pre-existing spinal cord. This conclusion followed from comparisons of mitotic indices in the central grey matter of spinal cords, proximal to the amputation plane, of animals intracoelomically injected with (a) retinoic acid 2 days before amputation and the mitotic inhibitor, demecolcine 5 h before sacrifice; or (b) as for the latter but without retinoic acid; or (c) only the solvent for (a) and (b). Animals were sacrificed concurrently, 9 days after tail amputation. In addition, the demecolcine treatment revealed the true mitotic activity of the spinal cord of axolotl to be at least five times greater than might otherwise have been suspected.
在美西螈幼体墨西哥钝口螈的尾巴再生过程中，视黄酸使已有的脊髓中的有丝分裂减少了约10倍。这一结论是通过比较以下几组动物脊髓中央灰质（靠近截肢平面）的有丝分裂指数得出的：（a）在截肢前2天腹腔内注射视黄酸且在处死前5小时注射有丝分裂抑制剂秋水仙碱的动物；（b）与（a）组类似但未注射视黄酸的动物；（c）仅注射（a）组和（b）组所用溶剂的动物。在尾巴截肢9天后，同时处死这些动物。此外，秋水仙碱处理显示美西螈脊髓的真实有丝分裂活性至少比原本怀疑的要高五倍。
