Patterns microvascular distribution of the colonic wall studied by electron microscopy: experimental study in rats

Background: The corrosion casting technique, known as the best method to study the three dimensional architecture of blood vessels in many organs, applied to the lower gastro intestinal (GI) tract was used to visualize the morphological patterns of small blood vessels supplying the colonic wall at scanning electron microscopy (SEM). Methods: 15 Wistar male rats weighing 300 g were deeply anaesthetised by an intraperitoneal injection of ketamine. An acrylic low viscosity resin was injected through the abdominal aorta before the origin of celiac trunk once it reached the superior and inferior mesenteric arteries; it filled marginal arteries, submucosal plexus, the perforant capillaries. The specimens were then observed in scanning electron microscope. Results: The vascular architecture of the colon that can be divided as followed: the major vessels, vessels supplying both longitudinal and circular muscular layers, the microvessels of submucosal plexus, and the mucosal vessels. Each layer of the colonic wall present its own vascular pattern with some difference regarding the mesenteric and antimesenteric site. Interpretation: Corrosion casting technique has demonstrated to be a useful method for the detailed comprehension of the vascular architecture of an organ as colon. Each layer of the colic wall present different and probably functional pattern that can be variable in the mesenteric or antimesenteric side