Go K G, Houthoff H J, Blaauw E H, Havinga P, Hartsuiker J
J Neurosurg. 1984 Apr;60(4):803-13. doi: 10.3171/jns.1984.60.4.0803.
Morphological and enzyme ultracytochemical evidence is presented to support the contention that the walls of arachnoid cysts secrete fluid. Clinical evidence has already suggested this phenomenon, including intracranial pressure elevation and expansion in some cases, and the observation that arachnoid cysts constitute closed compartments with a fluid content that cannot be derived from other cerebrospinal fluid-containing spaces. Ultrastructurally, the cyst lining showed a similarity to subdural neurothelium and the neurothelial lining of arachnoid granulations in such morphological features as intercellular clefts with sinusoid dilatations, desmosomal intercellular junctions (upon which tonofilaments may be abutting), pinocytotic vesicles, multivesicular bodies, lysosomal structures, and the presence of a basal lamina. Some of these features, together with the presence of microvilli on the luminal surface, are consistent with fluid secretion. Moreover, enzyme cytochemistry demonstrated (Na+ + K+)-ATPase in the plasma membranes lining the cavity, either directly (the apical membranes), or via the intercellular clefts (the basolateral membranes), and, with alkaline phosphatase occupying the opposite plasma membranes, this structural organization indicates fluid transport toward the lumen. It may be surmised that arachnoid cysts derive from subdural neurothelium differentiating towards arachnoid villus mesothelium.
本文提供了形态学和酶超微细胞化学证据，以支持蛛网膜囊肿壁分泌液体这一论点。临床证据早已提示了这一现象，包括某些病例中的颅内压升高和囊肿扩大，以及蛛网膜囊肿构成封闭腔室且其所含液体并非来自其他含脑脊液间隙的观察结果。在超微结构上，囊肿内衬在形态学特征上与硬脑膜下神经上皮及蛛网膜颗粒的神经上皮内衬相似，如具有窦状扩张的细胞间裂隙、桥粒样细胞间连接（张力丝可能与之邻接）、吞饮小泡、多囊体、溶酶体结构以及基膜的存在。其中一些特征，连同腔面微绒毛的存在，与液体分泌相符。此外，酶细胞化学显示，在腔内衬的质膜中，要么直接在顶端膜，要么通过细胞间裂隙在基底外侧膜检测到（钠 + 钾）-ATP 酶，且碱性磷酸酶位于相对的质膜上，这种结构组织表明液体向腔内运输。可以推测，蛛网膜囊肿源自向蛛网膜绒毛间皮分化的硬脑膜下神经上皮。
