Mathieu-Costello O, Potter R F, Ellis C G, Groom A C
Department of Medicine, University of California, San Diego 92093.
Microvasc Res. 1988 Jul;36(1):40-55. doi: 10.1016/0026-2862(88)90037-4.
It has been a matter of discussion whether the dramatic increase in capillary tortuosity visualized in shortened muscles by vascular cast represents in vivo situations. In this study, we combined vascular cast and stereological methods in the same samples, in order to obtain (1) measurements of sarcomere length in the same muscles from which corrosion casts were prepared, and (2) scanning electron micrographs of the three-dimensional arrangement of capillaries in the same muscles where capillary anisotrophy was estimated by morphometry. Various rat skeletal muscles (soleus, gastrocnemius, and gracilis) were examined at lengths ranging from full shortening to full extension. We found a very good correlation between capillary geometry in material prepared for vascular casts and in muscles perfusion-fixed in situ. All muscles, cast and noncast, showed the same progressive curvilinear decrease in capillary anisotropy with decreasing sarcomere length. Capillary tortuosity visualized by corrosion casts in shortened muscles is a consequence of fiber shortening, within physiological sarcomere lengths; it does not represent an artifact related to the casting procedure.
通过血管铸型观察到的缩短肌肉中毛细血管迂曲度的显著增加是否代表体内情况，一直是一个讨论的问题。在本研究中，我们在相同样本中结合了血管铸型和体视学方法，以便获得：（1）从制备腐蚀铸型的相同肌肉中测量肌节长度；（2）在通过形态计量学估计毛细血管各向异性的相同肌肉中，毛细血管三维排列的扫描电子显微照片。对各种大鼠骨骼肌（比目鱼肌、腓肠肌和股薄肌）在从完全缩短到完全伸展的长度范围内进行了检查。我们发现，为血管铸型制备的材料中的毛细血管几何形状与原位灌注固定的肌肉中的毛细血管几何形状之间存在非常好的相关性。所有肌肉，无论是铸型的还是未铸型的，随着肌节长度的减少，毛细血管各向异性均呈现相同的渐进性曲线下降。在缩短肌肉中通过腐蚀铸型观察到的毛细血管迂曲是纤维在生理肌节长度范围内缩短的结果；它并不代表与铸型过程相关的假象。
