【摘要】 为探讨松果体分泌物在细胞外转运到蛛网膜下隙脑脊液途径的结构基础,本研究运用透射电镜技术对成年大鼠松果体浅部进行了观察。结果显示:(1)大鼠松果体毛细血管为有孔型(孔径50nm),借基膜与宽阔的血管周隙分隔;(2)松果体细胞借基膜与结缔组织间隙分隔,松果体细胞之间形成与松果体囊结缔组织间隙及血管周隙相通的细胞间小管;(3)松果体囊表面为扁平上皮,上皮下为疏松结缔组织间隙,其内可见松果体细胞的胞体和突起。囊上皮细胞间存在瓣膜样连接(叶瓣间宽处可达1μm)和囊上皮孔(2.5μm)。以上结果提示,松果体细胞表面可分为结缔组织间隙面、连接面和细胞间小管面三个功能面,松果体分泌物可能通过血管周隙-细胞间小管-松果体囊结缔组织间隙-囊上皮瓣膜样连接或囊上皮孔,释放入蛛网膜下隙脑脊液中转运。更多还原

【Abstract】 To explore the structural foundation of a direct extracellular transport pathway of pineal secretions from pineal body to cerebrospinal fluid of subarachnoid space, the superficial pineal body of the rat was observed by transmission electron microscope. The results showed that: (1)The blood capillaries in the rat pineal body were endowed with fenestrated endothelium, separated from the broad perivascular space by basement membrane; (2)The pinealocytes were also separated from the connective tissue space by basement membrane.There were intercellular canaliculus between pinealocytes linking up with connective tissue space of pineal capsule and perivascular space; (3)The pineal capsule was composed of squamous epithelial cells and subepithelial loose connective tissue space. In subepithelial connective tissue space there existed pinealocytic body and processes. Some overlapped junctions(1 μm between parallel epithelial leaflets) and interepithelial openings(2.5μm) were observed among epithelial cells. The present results suggest that the pinealocytes have three types of functional surfaces: perivascular, intercellular and canalicular. The pineal secretions may be transported directly from pineal body to cerebrospinal fluid of subarachnoid space by pineal perivascular space-intercellular canaliculus- overlapped junctions / interepithelial openings among epithelial cells.更多还原