Rubányi G, Balogh I, Kovách A G, Somogyi E, Sótonyi P
Acta Morphol Acad Sci Hung. 1980;28(3):269-79.
General ultrastructure and subcellular calcium localization was studied in the longitudinal muscle layer of the rabbit's post partum myometrium by means of the lead acetate and potassium pyroantimonate cytochemical techniques. The finding of abundant surface vesicles (SV) and intracellular tubules of smooth endoplasmic reticulum (SER), their close contacts in some parts of the fibre, and the isolated compartment between plasma membrane (PM) and basal membrane (BM) may be important in the understanding of characteristic features of excitation-contraction coupling in this tissue. In the resting fibre (Mn2+-induced relaxation) the lead acetate and pyroantimonate reaction product was localized in the PM, SV, SER and mitochondria (M), indicating the possible in situ Ca-sequestering properties of the above structures. Tissues fixed at the peak of K+-contraction revealed abundant precipitates in the cytoplasm, while little reaction product was seen at the periphery of the fibre. The specificity of the cytochemical reactions was verified by Ca-extraction EGTA in situ (lead acetate) and by electronprobe X-ray microanalysis (pyroantimonate). These findings indicate that redistribution of the precipitate during the contraction-relaxation cycle is the result of intracellular calcium translocation in the rabbit myometrium.
运用醋酸铅和焦锑酸钾细胞化学技术，研究了兔产后子宫肌层纵行肌层的一般超微结构和亚细胞钙定位。发现丰富的表面小泡（SV）和平滑内质网（SER）的细胞内小管、它们在纤维某些部位的紧密接触以及质膜（PM）和基底膜（BM）之间的孤立间隔，对于理解该组织兴奋-收缩偶联的特征可能很重要。在静息纤维（Mn2+诱导的舒张）中，醋酸铅和焦锑酸盐反应产物定位于质膜、表面小泡、平滑内质网和线粒体（M），表明上述结构可能具有原位钙螯合特性。在K+收缩峰值时固定的组织，细胞质中有大量沉淀，而在纤维周边几乎看不到反应产物。通过原位Ca-螯合剂乙二醇双四乙酸（EGTA）（醋酸铅）和电子探针X射线微分析（焦锑酸盐）验证了细胞化学反应的特异性。这些发现表明，收缩-舒张周期中沉淀的重新分布是兔子宫肌层细胞内钙转运的结果。
