Frid M G, Shekhonin B V, Koteliansky V E, Glukhova M A
Institute of Experimental Cardiology, Cardiology Research Center, Moscow, Russia.
Dev Biol. 1992 Oct;153(2):185-93. doi: 10.1016/0012-1606(92)90104-o.
Expression of the regulatory contractile proteins, heavy caldesmon (h-caldesmon) and calponin was studied in human aortic smooth muscle cells (SMCs) during development and compared with the expression of alpha-SM-actin and smooth muscle-myosin heavy chain (SM-MHCs). For this study, novel monoclonal antibodies specific to SM-MHCs, h-caldesmon, and calponin were developed and characterized. Aortic SMCs from fetuses of 8-10 and 20-22 weeks of gestation express alpha-SM-actin and SM-MHCs, but neither h-caldesmon nor calponin were expressed as demonstrated by immunoblotting and immunofluorescence techniques. In the adult aortic tunica media, SMCs contain all four markers. Thus, the expression of calponin, similar to the expression of alpha-SM-actin, SM-MHCs, and h-caldesmon, is developmentally regulated in aortic SMCs. In the adult aortic subendothelial (preluminal) part of tunica intima, numerous cells containing SM-MHCs, but lacking h-caldesmon and calponin, were found. These results illustrate the similarity of SMCs from intimal thickenings and immature (fetal) SMCs. Expression of contractile proteins in the developing SMCs is coordinately regulated; however, distinct groups of proteins appear to exist whose expression is regulated differently. Actin and myosin, being major contractile proteins, also play a structural role and appear rather early in development, whereas caldesmon and calponin, being involved in regulation of contraction, can serve as markers of higher SMC differentiation steps. In contrast, h-caldesmon and calponin were already present in visceral SMCs (trachea, esophagus) of the 10-week-old fetus. These results demonstrate that the time course of maturation of visceral SMCs is different from that of vascular SMCs.
在发育过程中，研究了人类主动脉平滑肌细胞（SMC）中调节性收缩蛋白重钙调蛋白（h - caldesmon）和钙调蛋白的表达，并与α - SM - 肌动蛋白和平滑肌肌球蛋白重链（SM - MHCs）的表达进行了比较。在本研究中，开发并鉴定了针对SM - MHCs、h - 钙调蛋白和钙调蛋白的新型单克隆抗体。妊娠8 - 10周和20 - 22周胎儿的主动脉SMC表达α - SM - 肌动蛋白和SM - MHCs，但免疫印迹和免疫荧光技术显示，h - 钙调蛋白和钙调蛋白均未表达。在成人主动脉中膜，SMC含有所有四种标志物。因此，钙调蛋白的表达与α - SM - 肌动蛋白、SM - MHCs和h - 钙调蛋白的表达一样，在主动脉SMC中受到发育调控。在成人主动脉内膜的内皮下（腔前）部分，发现了许多含有SM - MHCs但缺乏h - 钙调蛋白和钙调蛋白的细胞。这些结果说明了内膜增厚处的SMC与未成熟（胎儿）SMC的相似性。发育中的SMC中收缩蛋白的表达受到协调调节；然而，似乎存在不同组的蛋白质，其表达受到不同的调节。肌动蛋白和肌球蛋白作为主要的收缩蛋白，也发挥结构作用，并且在发育早期就出现，而钙调蛋白和钙调蛋白参与收缩调节，可作为SMC更高分化阶段的标志物。相比之下，h - 钙调蛋白和钙调蛋白在10周龄胎儿的内脏SMC（气管、食管）中已经存在。这些结果表明，内脏SMC的成熟时间进程与血管SMC不同。
