Nadler J V, Evenson D A
Anat Embryol (Berl). 1982 Sep;165(1):113-23. doi: 10.1007/BF00304587.
The projection from the ventromedial septum to the fascia dentata was investigated autoradiographically in normal adult rats and in adult rats whose entorhinal cortex had been removed unilaterally at the age of 11 days. In the fascia dentata of normal rats and in the fascia dentata contralateral to the entorhinal lesion septohippocampal fibers and terminals were distributed just below and, to a lesser extent, just above the granular layer. The molecular layer above the supragranular zone was lightly and more or less uniformly innervated. Ipsilateral to the entorhinal lesion, however, the outer part of the dentate molecular layer received an anomalously dense septal projection (average 3-4 times the contralateral projection). The entorhinal lesion did not consistently affect the density of this projection in any other lamina. These results confirm that septohippocampal fibers increase their density of innervation when synaptic sites are made available by degeneration of lateral perforant path fibers during development. This represents a net increase in total septal innervation of the fascia dentata, not merely a change in the distribution of the projection among its target zones.
运用放射自显影技术，对正常成年大鼠以及在11日龄时单侧切除内嗅皮层的成年大鼠，研究了腹内侧隔区至齿状回的投射。在正常大鼠的齿状回以及与内嗅皮层损伤相对侧的齿状回中，隔海马纤维和终末分布于颗粒层下方，在较小程度上也分布于颗粒层上方。颗粒上层上方的分子层有轻度且大致均匀的神经支配。然而，在内嗅皮层损伤同侧，齿状分子层的外侧部分接受了异常密集的隔区投射（平均为对侧投射的3 - 4倍）。内嗅皮层损伤并未始终一致地影响其他任何层中该投射的密度。这些结果证实，在发育过程中，当外侧穿通路径纤维变性使突触位点可用时，隔海马纤维会增加其神经支配密度。这代表齿状回的总隔区神经支配净增加，而不仅仅是投射在其靶区之间分布的变化。
