Dregelid E, Haukaas S, Amundsen S, Eide G E, Søreide O, Lekven J, Svanes K
Am J Physiol. 1986 May;250(5 Pt 1):G670-8. doi: 10.1152/ajpgi.1986.250.5.G670.
Microspheres of 10.90 +/- 0.65 micron (SD) were injected in the superior mesenteric artery of cats and their intramural distribution and diameter in the small intestine were studied microscopically under basal conditions and after vasodilation by isoproterenol. Approximately 2% of the spheres were shunted through the small intestinal vasculature and could be recovered in the liver. Analysis of the tissue distribution suggested that all spheres arrested in villi represented villous blood flow, spheres arrested in the crypt layer represented flow to the crypts, and the majority of microspheres trapped in the submucosa also represented crypt flow. Nutritive blood flow to the submucosa constituted only 1.5% of total intestinal flow. Log-linear analyses identified factors responsible for sphere distribution, including effects of sphere size, isoproterenol treatment, and local blood flow or vascular resistance. Spheres with diameters greater than 11.08 micron had 1.35 times larger odds than smaller spheres to embolize in the muscularis rather than in the mucosa, but no consistent difference between diameter profiles in the crypts and villi was found. With this reservation, 11-micron spheres seem to be appropriate for measuring blood flow to the muscle, crypt, and villous layers of the small intestine.
将直径为10.90±0.65微米（标准差）的微球注入猫的肠系膜上动脉，在基础条件下以及异丙肾上腺素引起血管舒张后，通过显微镜研究微球在小肠壁内的分布及其直径。约2%的微球经小肠血管分流，可在肝脏中回收。组织分布分析表明，滞留在绒毛中的所有微球代表绒毛血流，滞留在隐窝层的微球代表流向隐窝的血流，而被困在黏膜下层的大多数微球也代表隐窝血流。黏膜下层的营养性血流仅占肠道总血流的1.5%。对数线性分析确定了影响微球分布的因素，包括微球大小、异丙肾上腺素处理以及局部血流或血管阻力的影响。直径大于11.08微米的微球栓塞在肌层而非黏膜层的几率比小直径微球大1.35倍，但在隐窝和绒毛的直径分布上未发现一致差异。基于此，11微米的微球似乎适合用于测量小肠肌层、隐窝和绒毛层的血流。
