Urabe Norio, Naito Ichiro, Saito Kenji, Yonezawa Tomoko, Sado Yoshikazu, Yoshioka Hidekatsu, Kusachi Shozo, Tsuji Takao, Ohtsuka Aiji, Taguchi Takehito, Murakami Takuro, Ninomiya Yoshifumi
Department of Molecular Biology and Biochemistry, Okayama University Graduate School of Medicine and Dentistry, Japan.
Arch Histol Cytol. 2002 Jun;65(2):133-43. doi: 10.1679/aohc.65.133.
We investigated the differential distribution of basement membrane type IV collagen a chains in the mouse brain by immunohistochemistry using a chain-specific monoclonal antibodies. Subendothelial basement membranes were found to contain alpha1 and alpha2 chains. Basement membranes surrounding smooth muscle cells on blood vascular walls were immunoreactive for alpha1 and alpha2 chains but not for alpha5 and alpha6 chains. Interestingly, the pia mater contained a thin basement membrane which was positive for alpha1, alpha2, alpha5, and alpha6 chains, suggesting that glia limitans superficialis coheres basement membranes containing [alpha1(IV)]2alpha2(IV) and [alpha5(IV)]2alpha6(IV) molecules. In contrast, capillaries always possessed thin basement membranes of [alpha1(IV)]2alpha2(IV) molecules. Cerebrospinal fluid is produced through filtration of blood at the choroid plexus, where two distinct basement membranes were detected by anti-al and anti-alpha2 antibodies. The subendothelial basement membrane appeared to consist of [alpha1(IV)]2alpha2(IV) molecules, whereas the subependymal basement membrane in the choroid plexus was strongly positive for alpha3, alpha4, and alpha5 chains, indicating that the filtering unit was composed of alpha3(IV)alpha4(IV)alpha5(IV) molecules. That the specific localizations of these molecules are shared by renal glomeruli and the choroid plexus leads us to hypothesize that the supramolecular network containing alpha3(IV) alpha4(IV)alpha5(IV) molecules may function as a permeability selective barrier.
我们使用链特异性单克隆抗体，通过免疫组织化学方法研究了小鼠脑中IV型胶原α链的差异分布。发现内皮下基底膜含有α1和α2链。血管壁上平滑肌细胞周围的基底膜对α1和α2链有免疫反应，但对α5和α6链无反应。有趣的是，软脑膜含有一层薄的基底膜，对α1、α2、α5和α6链呈阳性，这表明浅表胶质界膜黏附含有[α1(IV)]2α2(IV)和[α5(IV)]2α6(IV)分子的基底膜。相比之下，毛细血管总是具有由[α1(IV)]2α2(IV)分子组成的薄基底膜。脑脊液是通过脉络丛处血液的滤过产生的，在那里抗α1和抗α2抗体检测到两种不同的基底膜。内皮下基底膜似乎由[α1(IV)]2α2(IV)分子组成，而脉络丛中的室管膜下基底膜对α3、α4和α5链呈强阳性，表明滤过单位由α3(IV)α4(IV)α5(IV)分子组成。这些分子在肾小球和脉络丛中的特定定位相同，这使我们推测，含有α3(IV)α4(IV)α5(IV)分子的超分子网络可能起到渗透选择性屏障的作用。
