Segmental angioarchitecture of the testicular lobule in man.

There is a close correlation between the angioarchitecture of the human testis and its inner subdivision into testicular lobules. Serial sections from paraffin and epon-embedded testicular tissue were used to examine the angioarchitecture of the human testis, and computer-aided 3-D-reconstruction was used to demonstrate the correlation between blood vessels and tissue organization. The recurrent arteries arise from the centripetal arteries, and run in the central axis of the testicular lobule. At regular intervals of on average, 300 microns the segmental arteries arise from the recurrent artery, which supplies segments of the testicular parenchyma perpendicular to the long axis of the testicular lobules. Within such a segment, the segmental artery supplies the microvasculature, which is partly surrounded by Leydig cells and partly stands in close contact with the wall of the seminiferous tubules. The venous drainage occurs through the intralobular veins, which run to the periphery of the lobule (towards the septum). These veins lead into the septum and there they join the collecting veins. A lobule can have several segments depending on its size. The base of such a tissue segment is directed towards the septum whereas the top is directed towards the centre of the lobule. Sections of several seminiferous tubules can be found in such a segment. The flow of blood from the arterial to the venous side of the testicular circulation occurs radially from the centre of the lobule to the septum.