Vascular structure of splenic autografts in the rat kidney

Rat splenic tissue was autotransplanted into the kidney. 12 weeks after transplantation the autografts were observed by scanning electron microscopy. The autografts had regenerated almost completely by the end of the 12th week. A part of the splenic tissue invaded into the kidney and formed the splenic cords. Using vascular casting, 2 different types of the vascular anastomoses between the 2 tissues were recognized. One was formed into the infiltrated region, where the splenic vasculature conglomerated and connected in a complicated fashion with the renal vessels. The other type was simpler in structure; a few fine vessels formed bridges between the splenic and renal vascular structures. The results suggest that these anastomoses may play an important role in transmission of pathogenic information from the renal to the splenic tissue, resulting in a prompt immunoreaction.