An experimental
varicocele was created in the adult rat by partial
ligation of the left renal vein. There was a significant bilateral elevation of both testicular blood flow and temperature in the
varicocele animals (p less than 0.01). Mean testicular blood flow for control and
varicocele animals was 29.6 +/- 1.0 and 39.8 +/- 2.0 ml./min./100 gm. tissue, while mean testicular temperature was 34.4 +/- 0.1 and 35.3 +/- 0.2C, respectively. A left
orchiectomy was combined with a left
varicocele to determine if the left testis is essential for the right testicular response to a
varicocele. Elevation of right testicular blood flow was not altered by left
orchiectomy (p less than 0.05); however, right testicular temperature was no longer significantly increased. Mean right testicular blood flow and temperature for this group was 39.0 +/- 1.5 ml./min./100 gm. tissue and 34.2 +/- 0.15C, respectively. A left
sympathectomy was combined with a left
varicocele to ascertain if the right testicular response to the left
varicocele was mediated through a neural pathway. A significant bilateral increase in testicular blood flow was noted with a left
sympathectomy alone, and thereby masked the ability to evaluate the right testicular response to the simultaneous left
sympathectomy and
varicocele. Elevation of right testicular blood flow in response to the left
varicocele is independent of the presence of a left testis and any immune response it may stimulate. The role of the sympathetic nervous system as a mediator of the bilateral
varicocele effect remains undetermined.