胎儿髁状突骨上组织的凝集素亲和组织化学和超微结构

Lectin-binding Histochemical and Ultrastructural Studies on the Supraosseous Tissue of Mandibular Condyle in Human Fetus

目的观察胎儿颞下颌关节髁状突骨上组织表浅部随胎龄增长的发育分化过程，对其组织学特征及细胞来源进行探讨。方法水囊引产的胎儿４８例，光镜研究４３例，电镜研究５例，光镜研究方法包括ＨＥ染色及凝集素亲和组化染色。电镜研究的超薄切片经铀铅双染色后采用Ｈｕ－１２Ａ电镜观察。结果（１）凝集素亲和组化染色：ＲＣＡ－Ｉ染色较特殊，主要表现为在Ｉ带表浅部逐渐出现的ＲＣＡ－Ｉ阳性细胞带。在２６～３８周胎龄的标本中，Ⅱ带小血管内皮细胞及内皮细胞之间的基质呈同样的ＲＣＡ－ｌ强阳性反应。ＵＥＡ、ＳＪＡ、ＳＢＡ仅对Ｉ带有弱反应，对其余各带均无反应。（２）电镜观察：在Ｉ带最表浅部观察到一种圆形或椭圆形电子密度高而色暗的细胞。在１６周胎龄时偶见该类细胞，在２２周及其后的标本常见该类细胞在游离缘成对或成列存在。结论上述结果为胎儿髁状突骨上组织关节带细胞的来源与性质提供了新的形态学依据。

Our study was undertaken with the main object of establishing the distribution pattern of specific lectin-binding sites and the fine structure of articular zone of the supraosseous tissue of mandibular condyle,Methods 48 fetuses,ranging in age from l3 to 38 weeks,were studied with the lectin-binding histochemical technics(biotin-labelled lectins)and transmission electron microscope.Results The staining of RCA-I was quite particular.During l3 to l8 weeks of fetus age,there were only a few RCA-I positive cells in the superfacial part of STMC.After l9 weeks,the amount of RCA-I positive cells increased,and they gradtially became one continuous RCA-I positive cellular zone. The staining pattern ofvascular endothelium in proliferative zone was similar to the RCA一I positive cellular zone.The reactions of UEA,SJA,SBA were only found after l8 weeks and their weak reactions were restricted in art cular zone,A special cell type had also been recognized in the superfacial part of STMC on electron microscope study.They had both a high nuclear cytoplasmic ratio and high electron density.These presumed mesenchymal cells increased their number and changed their ultrastrtuture features as the fetus growing.Conclusion This studies had provided a new morphological eviclence of the origin and character of articular zone cells of STMC of human fetus.