Vasculature of the mouse, rat, and rabbit testis‐epididymis

Abstract

The arrangement of blood vessels serving the testis-epididymis vas investigated microscopically in the mouse, rat, and rabbit. Blood vessels were visualized by infusing liquid silicone rubber into the vessels and subsequently clearing the surrounding tissue. Comprehensive illustrations of the vasculature were prepared from three-dimensional examinations. Arterial and venous vessels serving the testis-epididymis follow similar routes in all three species. However, the arrangements and characteristics of the blood vessels demonstrate dramatic species differences. For example, arteries within the testes have tight coils in the mouse and artery-artery anastomoses in the rat. Veins form vascular pathways that connect the testis and efferent ductules in all three species but also form a connection between the testis and cauda epididymidis in the rabbit only. Testosterone concentrations were determined in blood obtained by micropuncture of selected testis-epididymal veins. The measurements establish that the highest levels of testosterone are found in testicular surface veins. Also, vas deferential veins of the rabbit had significant amounts of testosterone. Studies of the blood-vessel volumes suggested that the volumes of arteries and veins in the testis are similar, whereas venous volumes exceed arterial volumes in all of the other organs examined. The studies provide comprehensive information about the architecture and physiology of blood vessels serving the testis-epididymis in the mouse, rat, and rabbit. Each species exhibits diversity in the vasculature and testosterone content of the veins. Veins connecting the testis to the efferent ductules and cauda epididymidis may provide for the preferential delivery of testicular secretions to androgen-dependent organs before the secretions are metabolized or diluted in the systemic blood.

Male contraception via simultaneous knockout of α 1A -adrenoceptors and P2X1-purinoceptors in mice

“…The cauda epididymis and vas deferens lie on the abdominal side of the blood-testis barrier in mice and receive their blood supply predominantly from branches of the deferential artery (22). This is anterior to the blood-testis barrier, and the vas deferens subsequently receives similar blood to other genitourinary and visceral organs.…”

Vasculature of Testis, epididymis and ductus deferens of Rabbit. The Arteries.

“…This problem has been studied, to a much lesser degree, in the mouse (Harrison 1949;Harrison and Weiner 1949;Froud 1959;Suzuki 1982;Chubb and Desjardins 1982), the guinea pig (Cooper and Schiller 1975), the golden hamster (Michel 1959) and in the rabbit (Harrison 1949;Harrison and Weiner 1949;Chubb and Desjardins 1982).…”

“…Similarly, in laboratory animals such study is necessary for experiments which, to a greater or lesser degree, provide knowledge which could be applied not only to domestic mammals, but also to man. Examples include the study of the effect of heavy metals on the testicular parenchyma, the effect of ionizing radiation, the effect of some medicaments, disorders in the circulation of the blood, as well as various experimental surgical interventions.Among laboratory animals, perhaps the vascularization of the rat testis has been studied the most ( H a r r i s o n 1949; H a r r i s o n and W e i n e r 1949; K o r m a n o 1967; V r z g u l o v á and Hajovská 1968;Hebel and Stromberg 1976;Chubb and Desjardins 1982;Melman et al 1985). This problem has been studied, to a much lesser degree, in the mouse (Harrison 1949;Harrison and Weiner 1949;Froud 1959;Suzuki 1982;Chubb and Desjardins 1982), the guinea pig (Cooper and Schiller 1975), the golden hamster (Michel 1959) and in the rabbit (Harrison 1949;Harrison and Weiner 1949;Chubb and Desjardins 1982).…”

Microvasculature of the buffalo epididymis

“…Epididymis segment differences have also been noted in the bull (Hees et al, 1989), boar (Stoffel et al, 1990), mouse (Suzuki, 1982;Abe et al, 1984), rat, rabbit (Chubb and Desjardins, 1982), and man (Kormano and Reijonen, 1976). Stoffel et al (1990), in a study of the boar, observed differences in the organization of the epididymis capillary networks of the caput, as compared to those of the corpus-cauda segments.…”

“…In particular, the microvasculature of the epididymis, and the absorptive and secretive processes of the epididymis epithelium are morphofunctional prerequisites for the capacity of sperm to fertilize. Past studies of the epididymis microvasculature have mostly focused on laboratory mammals (Clavert et al, 1980;Chubb and Desjardins, 1982;Suzuki, 1982;Abe et al, 1984;Markey and Meyer, 1992), large breeding mammals (Hees et al, 1989;Stoffel et al, 1990), and man (Kormano and Reijonen, 1976). However, few of these studies dealt with species exhibiting seasonal sexual activity, and they revealed very little regarding the role that vascular structures play in the regulation of nutrition and hormone exchanges.…”