Brauer K, Holzer M, Brückner G, Tremere L, Rasmusson D D, Poethke R, Arendt T, Härtig W
Department of Neuroanatomy, Paul Flechsig Institute for Brain Research, University of Leipzig, D-04109 Leipzig, Germany.
J Comp Neurol. 1999 Sep 13;412(1):112-22. doi: 10.1002/(sici)1096-9861(19990913)412:1<112::aid-cne8>3.0.co;2-m.
The present study focused on cholinergic neurons in the lateral septal region of the raccoon detected by choline acetyltransferase (ChAT)-immunostaining. For comparison of the cholinergic neurons of the medial and lateral septal nuclei, soma sizes were measured, and several antibodies were applied that differentially characterize these cells in several species: low-affinity neurotrophin receptor p75 (p75(NTR)), calbindin-D(28k) (CALB), and constitutive nitric oxide synthase (cNOS). To compare the basic organization of the raccoon septum with that in other mammals, parvalbumin (PARV) immunocytochemistry and Wisteria floribunda-agglutinin (WFA) lectin histochemistry also were used in double-staining experiments. The ChAT-immunoreactive neurons of the rostral lateral septum are arranged in laminae. Accumulations of cholinergic varicosities, often clearly ensheathing noncholinergic neurons, occupy small territories of the rostral septum. Such regions become larger in the caudal septum. They are assumed to correspond to the septohippocampal and septofimbrial nuclei of the rat. In contrast to the large medial septal cholinergic neurons of the raccoon that contain p75(NTR), CALB, and cNOS, the cholinergic neurons of the lateral septum are smaller and do not express these markers. A further peculiarity is that the region of the lateral septum that contains cholinergic neurons corresponds to WFA-labelled extracellular matrix zones that contain chondroitin sulfate proteoglycans. In addition to clustered thread- or ring-like accumulations of the WFA, sparsely labelled perineuronal nets surround the lateral septal cholinergic neurons. Similar to other species that have been investigated, perineuronal nets are completely absent around cholinergic cells of the medial septum. The PARV-containing neurons of this region, however, are enwrapped by perineuronal nets as they are in the rat. Within the medial septum, the PARV-containing neurons are restricted to ventral bilateral territories that are devoid of cholinergic cells. In this respect, they differ from the more vertically arranged PARV-containing medial septal cells in rodents and primates. Apart from striking differences in numbers and distribution patterns, the raccoon lateral septal cholinergic neurons resemble those detected by Kimura et al. (Brain Res [1990] 533:165-170) in the ventrolateral septal region of rat and monkey. Their participation in the functions of the lateral septum remains to be elucidated.
本研究聚焦于通过胆碱乙酰转移酶（ChAT）免疫染色检测浣熊外侧隔区的胆碱能神经元。为了比较内侧和外侧隔核的胆碱能神经元，测量了其胞体大小，并应用了几种能在多个物种中对这些细胞进行差异表征的抗体：低亲和力神经营养因子受体p75（p75(NTR)）、钙结合蛋白-D(28k)（CALB）和组成型一氧化氮合酶（cNOS）。为了将浣熊隔区的基本组织结构与其他哺乳动物的进行比较，在双重染色实验中还使用了小白蛋白（PARV）免疫细胞化学和紫藤凝集素（WFA）组织化学。吻侧外侧隔区的ChAT免疫反应性神经元呈层状排列。胆碱能曲张体的聚集，常常清晰地包裹着非胆碱能神经元，占据吻侧隔区的小区域。在尾侧隔区，这些区域会变大。它们被认为对应于大鼠的隔海马核和隔纤维核。与浣熊内侧隔区含有p75(NTR)、CALB和cNOS的大型胆碱能神经元不同，外侧隔区的胆碱能神经元较小，且不表达这些标志物。另一个特点是，外侧隔区中含有胆碱能神经元的区域对应于含有硫酸软骨素蛋白聚糖的WFA标记的细胞外基质区。除了WFA呈簇状的线状或环状聚集外，稀疏标记的神经元周围网围绕着外侧隔区的胆碱能神经元。与已研究的其他物种类似，内侧隔区的胆碱能细胞周围完全没有神经元周围网。然而，该区域含PARV的神经元如在大鼠中一样被神经元周围网包裹。在内侧隔区内，含PARV的神经元局限于腹侧双侧区域，这些区域没有胆碱能细胞。在这方面，它们与啮齿动物和灵长类动物中更垂直排列的内侧隔区含PARV的细胞不同。除了数量和分布模式上的显著差异外，浣熊外侧隔区的胆碱能神经元类似于Kimura等人（《脑研究》[1990]533:165 - 170）在大鼠和猴子腹外侧隔区检测到的神经元。它们在外侧隔区功能中的作用仍有待阐明。
