Roelofs M, Wein A J, Monson F C, Passerini-Glazel G, Koteliansky V E, Sartore S, Levin R M
Division of Urology, University of Pennsylvania, Philadelphia 19104, USA.
J Appl Physiol (1985). 1995 Apr;78(4):1432-41. doi: 10.1152/jappl.1995.78.4.1432.
Partial outlet obstruction of rabbit bladder induces serosal thickening and smooth muscle (SM) cell hypertrophy that are accompanied by phenotypic changes in the expression of cytoskeletal and cytocontractile proteins. In the present study, we compare the observed progressive phenotypic changes with the contractile responses of strips of the thickened serosa. At 15 days after partial outlet obstruction, although cells in thickened serosa demonstrate the presence of nonmuscle (NM) myosin of A-like type, vimentin, and SM alpha-actin, no contractile responses of this tissue were noted. At later times (30 days), this tissue expressed in addition SM myosin, and this pattern was paralleled by the development of KCl-stimulated contractility. It is only after 60 days that the serosa demonstrated the expression of desmin, phosphoglucomutase (PGM)-related protein, and was locally negative for NM myosin, indicating a maturation toward adult SM cells. Concomitant to this phenotypic change, the response to KCl increased, and a bethanechol-stimulated contractile response developed. At no time period did the serosal layer react with anti-synaptophysin or anti-neurofilament proteins nor did the strips respond to field stimulation (via release of neurotransmitters), showing that SM cell differentiation and development of contractile responses during serosal thickening are independent of innervation.
兔膀胱部分出口梗阻可导致浆膜增厚和平滑肌（SM）细胞肥大，同时伴有细胞骨架和细胞收缩蛋白表达的表型变化。在本研究中，我们将观察到的渐进性表型变化与增厚浆膜条带的收缩反应进行了比较。部分出口梗阻后15天，尽管增厚浆膜中的细胞显示存在A类非肌肉（NM）肌球蛋白、波形蛋白和SMα-肌动蛋白，但未观察到该组织的收缩反应。在后期（30天），该组织还表达了SM肌球蛋白，并且这种模式与KCl刺激的收缩性发展平行。只有在60天后，浆膜才显示结蛋白、磷酸葡萄糖变位酶（PGM）相关蛋白的表达，并且局部NM肌球蛋白呈阴性，表明向成年SM细胞成熟。伴随这种表型变化，对KCl的反应增加，并且出现了氨甲酰甲胆碱刺激的收缩反应。在任何时间段，浆膜层都不与抗突触素或抗神经丝蛋白反应，条带也不响应场刺激（通过神经递质释放），这表明浆膜增厚过程中SM细胞的分化和收缩反应的发展与神经支配无关。
