Functional arterio-venous anastomoses between the testicular artery and the pampiniform plexus in the spermatic cord of rams

Abstract

Summary. Blood flow to the testis, haemoglobin oxygen saturation and testosterone concentration in arterial and venous testicular blood vessels were studied in Texel rams in the breeding and non-breeding season.Blood flow in the proximal and distal testicular artery was measured electromagnetically. The mean flow in the proximal testicular artery was 18\m=.\5 ml/min and in the distal testicular artery 7\m=.\5 ml/min, and there was no detectable seasonal influence.Haemoglobin oxygen saturation and testosterone concentration were measured in the saphenous artery and vein, the distal testicular artery and vein, and in the proximal testicular vein. The haemoglobin oxygen saturation in the proximal testicular vein was significantly higher than in the distal testicular vein in both seasons. The mean testosterone concentration was significantly lower in the proximal testicular vein than in the distal testicular vein in both seasons. Based on haemoglobin oxygen saturation and testosterone data, it was calculated that between 28 and 46% of the testicular arterial blood was bypassing the testis and was directly flowing through arterio-venous anastomoses towards the pampiniform plexus in the spermatic cord of conscious rams. In anaesthetized rams 55 and 64% of the blood was flowing directly from the testicular artery to the pampiniform plexus based on blood flow data.Transfer of testosterone and oxygen by passive diffusion from the testicular artery to the pampiniform plexus and vice versa in the spermatic cord was not detected.

Angioarchitecture of the human spermatic cord

“…In all species investigated, a tightly organized venous network around the testicular artery has been described, with certain species-specific differences (Hess et al 1984;Ohtsuka 1984;Weerasooriya and Yamamoto 1985;Noordhuizen-Stassen et al 1985;Rerkamnuaychoke et al 1991a). Several functions have been assigned to this intimate association between the testicular artery and the pampiniform plexus, viz.…”

Testicular arteries systematization based on different levels of scrotal configuration in caprines

“…In the literature, mainly concerning ovine species, descriptions about the vascular arrangement of the spermatic funiculus have been observed (NOORDHUIZEN-STASSEN et al, 1985;CARVALHAL et al, 2000) and little attention has been given to caprine species (SOUZA et al, 1992;OLIVEIRA et al, 2002). No report was found on vascular configuration in caprines testicles with scrotal bipartition.…”

Testicular microvascularization in the common tree shrew (Tupaia glis) as revealed by vascular corrosion cast/SEM and by TEM

“…The species having testes permanently lodged in the abdominal cavity have a straight testicular artery without pampiniform plexus (Glover, 1973;Short et al, 1967). Those with scrotal testes have a coiled testicular artery with pampiniform plexus (Christensen, 1964;Chubb and Desjardins, 1982;Dhingra, 1979;Ohtsuka, 1984;Osman et al, 1979;Noordhuizen-Stassen et al, 1985;Sisson, 1969). In most animals with scrotal testis, the testicular artery encircles the gland on the capsular surface before arteriolization into the testicular tissue (Chubb and Desjardins, 1982;Suzuki, 1982) but, in man, the artery does not surround the gland and it sends off many branches before or upon reaching the surface of the testis (Kormano and Suoranta, 1971).…”