Faggian L, Pampinella F, Roelofs M, Paulon T, Franch R, Chiavegato A, Sartore S
Department of Biomedial Sciences, University of Padua, Italy.
Histochem Cell Biol. 1998 Jan;109(1):25-39. doi: 10.1007/s004180050199.
We have studied the phenotypic changes in regenerating smooth muscle (SM) tissue of detrusor muscle after local application of a necrotizing, freeze-thaw injury to the serosal surface of rabbit bladder. Bromo-deoxyuridine (BrdU) incorporation and immunofluorescence studies were performed on bladder cryosections from day 2 up to day 15 after surgery with monoclonal antibodies specific for some cytoskeletal markers [desmin, vimentin, non-muscle (NM) myosin] and for SM-specific proteins (alpha-actin, myosin, and SM22). Four days after lesion, some clls incorporated in regenerating SM bundles are BrdU positive, but all display a phenotypic pattern identical to that of the interstitial, highly proliferating cells, i.e., expression of vimentin. By days 7-15 the differentiation profile of regenerating SM returns to that of uninjured SM tissue (appearance of desmin, SM-type alpha-actin, and SM myosin). A chemical denervation achieved by 6-hydroxydopamine treatment for 2 weeks induces the formation of vimentin/SM alpha-actin/NM myosin/SM22-containing myofibroblasts in the interstitial, fibroblast-like cells of uninjured bladder. In the bladder wall, alteration of reinnervation during the regenerating SM process produces: (1) in the outer region, the activation of vimentin/SM alpha-actin/desmin myofibroblasts in the de novo SM cell bundles; and (2) in the inner region of bladder, including the muscularis mucosae, the formation of proliferating, fully differentiated SM cells peripherally to newly formed SM cell bundles. These findings suggest that: (1) the de novo SM tissue formation in the bladder can occur via incorporation of interstitial cells into growing SM bundles; and (2) the alteration of reinnervation during the regenerating process induces a spatial-specific differentiation of interstitial myofibroblasts in SM cells before SM cell bundling.
我们研究了兔膀胱浆膜面局部应用坏死性冻融损伤后逼尿肌再生平滑肌（SM）组织的表型变化。术后第2天至第15天，使用针对某些细胞骨架标记物[结蛋白、波形蛋白、非肌肉（NM）肌球蛋白]和SM特异性蛋白（α-肌动蛋白、肌球蛋白和SM22）的单克隆抗体，对膀胱冰冻切片进行溴脱氧尿苷（BrdU）掺入和免疫荧光研究。损伤后4天，再生SM束中一些掺入的细胞BrdU呈阳性，但所有细胞均表现出与间质中高度增殖细胞相同的表型模式，即波形蛋白表达。到第7 - 15天，再生SM的分化谱恢复到未损伤SM组织的分化谱（结蛋白、SM型α-肌动蛋白和SM肌球蛋白出现）。用6-羟基多巴胺处理2周实现的化学去神经支配，在未损伤膀胱的间质成纤维样细胞中诱导形成含波形蛋白/SMα-肌动蛋白/NM肌球蛋白/SM22的肌成纤维细胞。在膀胱壁中，再生SM过程中神经再支配的改变产生：（1）在外部区域，新生SM细胞束中波形蛋白/SMα-肌动蛋白/结蛋白肌成纤维细胞的激活；（2）在膀胱内部区域，包括黏膜肌层，在新生SM细胞束周围形成增殖的、完全分化的SM细胞。这些发现表明：（1）膀胱中新生SM组织的形成可通过间质细胞掺入生长的SM束发生；（2）再生过程中神经再支配的改变在SM细胞成束之前诱导间质肌成纤维细胞在SM细胞中发生空间特异性分化。
