Inoue K, Terashima T, Inoue Y
Department of Anatomy, Hokkaido University School of Medicine, Sapporo, Japan.
Brain Res Dev Brain Res. 1991 Sep 19;62(1):146-50. doi: 10.1016/0165-3806(91)90201-s.
To determine whether or not the intracortical distribution pattern of pyramidal tract (PT) neurons in the motor cortex (hindlimb area) of normal and reeler mutant mice changes during early postnatal development of the cortex, we injected HRP into the pyramidal decussation of postnatal day (P) 8 and adult animals of the normal and reeler strains, and killed the animals 2 days later. In the normal P10 and adult mice, such an injection resulted in a band of labelled neurons confined to the layer of large pyramids (LP), suggesting that the intracortical localization of PT neurons does not change from P10 to adulthood in the normal strain. In the P10 and adult reeler mice, labelled PT neurons were scattered radially from the deepest zone to the superficial zone of the motor cortex. However, while the HRP-labelled PT neurons are located bilaminarly in both the deepest zone and the superficial zone of the motor cortex of the P10 reeler mouse, the majority of PT neurons were found in the upper third of the motor cortex of the adult reeler mouse. Thus, the intracortical distribution pattern of PT neurons of the reeler mouse changes during the postnatal period.
为了确定正常小鼠和reeler突变小鼠运动皮层（后肢区域）中锥体束（PT）神经元的皮质内分布模式在皮层出生后早期发育过程中是否发生变化，我们将辣根过氧化物酶（HRP）注入出生后第8天（P8）的正常和reeler品系成年动物的锥体交叉处，并在2天后处死动物。在正常的P10和成年小鼠中，这种注射导致一条标记神经元带局限于大锥体层（LP），这表明在正常品系中，PT神经元的皮质内定位从P10到成年期不会改变。在P10和成年reeler小鼠中，标记的PT神经元从运动皮层的最深区域到最浅区域呈放射状散布。然而，虽然在P10 reeler小鼠运动皮层的最深区域和最浅区域中，HRP标记的PT神经元呈双层分布，但在成年reeler小鼠运动皮层的上三分之一区域中发现了大多数PT神经元。因此，reeler小鼠PT神经元的皮质内分布模式在出生后时期会发生变化。
