Lewis E R, Cotman C W
Neuroscience. 1983 Jan;8(1):57-66. doi: 10.1016/0306-4522(83)90025-8.
In previous experiments we have studied the development of grafts of embryonic septal tissues implanted alongside the hippocampal formation of neonatal rats. In the present study we examined intracerebral implants of corpus striatum, a brain region that contains acetylcholinesterase-positive cells and does not normally project to the hippocampal formation, in order to evaluate the possibility that neurotransmitter identity may be involved in mechanisms guiding patterns of afferent growth and connectivity. Implant cavities were made in the entorhinal cortices of neonatal rat recipients and 3-6 days later embryonic striatal tissues were grafted to these preformed cavities. Implants were examined with acetylcholinesterase histochemistry one month after implantation. Grafts of embryonic striatal tissues did not survive implantation when the implant was introduced at the same time as the cavity was made. Grafts of corpora striata containing acetylcholinesterase-positive neurons were found in 7 of 11 rats in the delayed implant paradigm and, in all but one of these animals, acetylcholinesterase was present within those terminal laminae in the ipsilateral hippocampus and dentate gyrus that normally receive cholinergic input from the septal area. These findings suggest that cues underlying the development of specific connections between native (and implanted) septal efferents and hippocampal target neurons may be recognized by ingrowing acetylcholinesterase-reactive fibers from striatal implants.
在之前的实验中，我们研究了将胚胎隔区组织移植到新生大鼠海马结构旁的发育情况。在本研究中，我们检查了纹状体的脑内植入物，纹状体是一个包含乙酰胆碱酯酶阳性细胞且通常不投射到海马结构的脑区，目的是评估神经递质特性可能参与引导传入生长和连接模式机制的可能性。在新生大鼠受体的内嗅皮质中制作植入腔，3 - 6天后将胚胎纹状体组织移植到这些预先形成的腔中。植入一个月后用乙酰胆碱酯酶组织化学法检查植入物。当与制作腔同时植入时，胚胎纹状体组织的移植未能存活。在延迟植入模式下，11只大鼠中有7只发现了含有乙酰胆碱酯酶阳性神经元的纹状体移植，除一只动物外，在所有这些动物同侧海马和齿状回的那些通常接受来自隔区胆碱能输入的终末层中都存在乙酰胆碱酯酶。这些发现表明，来自纹状体植入物的向内生长的乙酰胆碱酯酶反应性纤维可能识别出天然（和植入）隔区传出纤维与海马靶神经元之间特定连接发育的潜在线索。
