Dipartimento di Fisiopatologia e dei Trapianti, Sezione di Fisiologia Umana, Università degli Studi di Milano, Milan, Italy.
Respir Physiol Neurobiol. 2013 Aug 1;188(1):60-5. doi: 10.1016/j.resp.2013.05.003. Epub 2013 May 10.
Coefficient of kinetic friction (μ) of pleural mesothelium has been found to increase markedly after mesothelial blotting and rewetting. This increase disappeared after addition of a solution with hyaluronan or sialomucin, though previous morphological studies showed that only sialomucin occurs in mesothelial glycocalyx. In this research we investigated whether μ of rabbit pleural mesothelium increased after hyaluronidase, neuraminidase or pronase treatment. Hyaluronidase and neuraminidase did not increase μ, though neuraminidase cleaved sialic acid from mesothelial glycocalyx of diaphragm specimens, and removed hystochemical stain of sialic acid from glycocalyx. Sialomucin treated with neuraminidase lowered μ of blotted mesothelium, though less than untreated sialomucin; this feature plus lubrication provided by other molecules could explain why μ did not increase after neuraminidase. Short pronase treatment (in order to affect only glycocalyx proteins) increased μ; this increase was removed by hyaluronan or sialomucin. After pronase treatment μ decreased with increase in sliding velocity, indicating a regime of mixed lubrication, as in blotted mesothelium.
胸膜间皮的动摩擦系数（μ）在间皮擦拭和再润湿后明显增加。添加含有透明质酸或唾液酸粘蛋白的溶液后，这种增加消失了，尽管之前的形态学研究表明只有唾液酸粘蛋白存在于间皮糖萼中。在这项研究中，我们研究了兔胸膜间皮在透明质酸酶、神经氨酸酶或胰蛋白酶处理后μ是否增加。透明质酸酶和神经氨酸酶并没有增加μ，尽管神经氨酸酶从膈标本的间皮糖萼中裂解了唾液酸，并从糖萼中去除了唾液酸的组织化学染色。用神经氨酸酶处理的唾液酸粘蛋白降低了擦拭后的间皮μ，但低于未处理的唾液酸粘蛋白；这种特性加上其他分子提供的润滑作用可以解释为什么神经氨酸酶处理后μ没有增加。短时间的胰蛋白酶处理（为了只影响糖萼蛋白）增加了μ；透明质酸或唾液酸粘蛋白可去除这种增加。用胰蛋白酶处理后，μ随滑动速度的增加而降低，表明存在混合润滑状态，如在擦拭后的间皮中。
