3-DIMENSIONAL DISTRIBUTION OF EXTRACELLULAR-MATRIX IN THE MOUSE SMALL-INTESTINAL VILLI - LAMININ AND TENASCIN

To investigate the three-dimensional distribution of laminin and tenas cin in the villi of the mouse small intestine, we designed a new tissu e preparation procedure for confocal laser scanning microscopy. Fixed tissue was pretreated with sodium deoxycholate and immunostained. The specimens displayed intense immunofluorescence even in the deeper site s of the lamina propria, Laminin was distributed like a sheet in the b asement membrane of the epithelium as well as that of the capillaries. Additionally, it was associated with some tubular structures in the l amina propria. Many pores were found in the laminin sheet, By comparis on, tenascin was distributed at the epithelial basement membrane and i n the underlying connective tissue exhibiting a striped pattern, Tenas cin was observed wrapping around the capillary wall in a spiral but wa s absent at the tip of the villi except in the capillary wall, Pores i n the staining pattern of tenascin were also found as was the case for laminin. This three-dimensional reconstruction made it possible to ob serve more clearly the localization of these two extracellular matrix molecules.