Experimental varicocele in the rat--a new experimental model. I. Effect on testicular structure.

A new experimental model of a varicoele in the rat is proposed. The study has been carried out on the Wistar rat in which the gonadal vein enters into the iliac vein. A varicocoele was induced in different ways: by complete or incomplete ligature of the iliac vein medial to the entry of the gonadal bein (Group I and II); by creating a venous compression by positioning the iliac artery in front of the vein, thus reproducing the so called "nut cracker" phenomenon (Group III); by creation of a small arterio-venous fistula by means of a side-to-side anastomosis between the iliac artery and vein. The results were studied macroscopically and histologically. The damage was most evident in Group III and significant in Group IV, but the absence of damage to the contralateral testis remains unexplained.