Scanning electron microscopy of the rabbit gallbladder mucosal microvasculature.

The arrangement of the microvasculature of the rabbit gallbladder was studied by means of scanning electron microscopy (SEM) of vascular corrosion casts and parallel uncorroded samples, together with correlated light microscopy (LM) observations. The outer layers of the gallbladder wall possess a coarse capillary network supplied by long and straight vessels which also give off numerous smaller twigs for the mucosal layer. Thin richly branched and anastomosing capillaries originate from the mucosal twigs. The mucosal capillaries are arranged in structures having a bowl-like configuration with the convexity facing towards the serosal layer, and the concavity corresponding to the epithelial lacunae seen by SEM of uncorroded samples. These structures were polygonal or irregularly rounded, and limited by vessels arranged in folds. The vessels running in these folds were capillaries and/or venules. The vascular folds corresponded to the epithelial folds demonstrated by SEM and LM of uncorroded samples.