Ogawa Y, Toyosawa S, Inagaki T, Hong S S, Ijuhin N
Department of Oral Pathology, Osaka University Faculty of Dentistry, Japan.
Histochem Cell Biol. 1995 May;103(5):387-94. doi: 10.1007/BF01457814.
Using monoclonal antibody specific to rat carbonic anhydrase isozyme VI (CA VI), the isozyme was localized in the lacrimal gland. A minority of acini (less than 10% of the total) contained a few immunoreactive acinar cells. Enzyme histochemistry indicated that the CA VI-positive cells were the only cells possessing CA in the lacrimal acini. In the acinar cells, the reaction product for CA VI was distributed in the secretory granules and cytosol between secretory granules. Except for mitochondrial enzyme (CA V) activity, the intracellular distribution of enzyme activity was similar to that of CA VI immunoreactivity, suggesting that rat lacrimal acinar cells contain only CA VI and CA V. CA VI in the secretory granules was discharged into the acinar lumen and is considered to carry out its function on the surface of the conjunctiva and cornea. The cytosolic CA VI may function in situ and be involved in electrolyte and water secretion by the acinar cells. Polyclonal antibody to rat erythrocyte CA (CA I and CA II) stained only the interlobular ducts. In contrast, all the ductal elements exhibited CA enzyme activity. This discrepancy between immunohistochemistry and enzyme histochemistry suggests the presence of CA isozyme(s) other than CA I, CA II and CA VI in the lacrimal duct.
利用针对大鼠碳酸酐酶同工酶VI（CA VI）的单克隆抗体，将该同工酶定位在泪腺中。少数腺泡（占总数的不到10%）含有一些免疫反应性腺泡细胞。酶组织化学表明，CA VI阳性细胞是泪腺腺泡中唯一具有碳酸酐酶的细胞。在腺泡细胞中，CA VI的反应产物分布在分泌颗粒以及分泌颗粒之间的胞质溶胶中。除了线粒体酶（CA V）活性外，酶活性的细胞内分布与CA VI免疫反应性相似，这表明大鼠泪腺腺泡细胞仅含有CA VI和CA V。分泌颗粒中的CA VI被排入腺泡腔，被认为在结膜和角膜表面发挥其功能。胞质溶胶中的CA VI可能在原位发挥作用，并参与腺泡细胞的电解质和水分泌。针对大鼠红细胞CA（CA I和CA II）的多克隆抗体仅对小叶间导管进行染色。相比之下，所有导管成分均表现出碳酸酐酶活性。免疫组织化学和酶组织化学之间的这种差异表明泪腺导管中存在除CA I、CA II和CA VI之外的其他碳酸酐酶同工酶。
