The Vasa Efferentia in the Rat and Mouse

Abstract

According to Wakeley (1943-44), the majority of epididymal cysts in man arise in the vasa efferentia, the bridge of tissue between the testis and epididymis. The ability of two sterilant chemicals to produce specific lesions of this nature in the rat (\g=a\-chlorhydrin\p=m-\Ericsson,1970; ethylenedimethanesulphonate\p=m-\Cooper & Jackson, 1970) points to the need for further information on the vasa efferentia in relation to their susceptibility to damage in this manner. As there appears to be inadequate information on the course of these tubules, the present study was undertaken.At post mortem, the testes resting in the scrotum of the rat present anterior and posterior surfaces and medial and lateral rounded borders. Serial longitudinal sections were made in both rat and mouse of the entire testis-epididymisvas complex, from the anterior to the posterior surface. In sections from a number of rats, it was observed that the rete testis penetrates into the tunica albuginea and from it, two channels of vasa efferentia emerge (Pl. 1 , Fig. 1); the arrangement is similar in the mouse (Pl. 1, Fig. 4). In the rat, both tubules become convoluted in relation to a non-tortuous artery and vein, which are branches of the superior epididymal vessels. The two channels and the blood vessels ascend in a column of fat covered by a peritoneal layer, inclining slightly laterally and posteriorly. In its ascent, each passes behind the caput epididymidis to a variable distance above it. There, the tubules arch medially and anteriorly (the arch, PI. 1, Figs. 2 and 3) and gain the upper margin of the proximal caput into which the vasa efferentia become incorporated (PI. 1, Fig. 3). It is at the arch that the nutrient vessels join the tubules from the lateral aspect. The vasa efferentia are relatively large at their origin from the rete testis (PI. 2, Figs. 5 and 6) and become smaller as they approach their union with the caput. A single layer of cubical to columnar epithelium supported by delicate fibres forms the wall, while stroma envelops them. Invariably, the vasa are empty in sections of normal specimens.According to Cunningham (1928), the vasa efferentia of the rat leave the testis, pass dorsal to the epididymis and join the anterior lobe of the caput. Harrison (1953)

Blind‐ending tubules and branching patterns of the rat ductuli efferentes

“…Estimates of the number of efferent ductules arising from the rat rete testis have varied substantially, ranging from 2-3 ductuli efferentes (Gier and Marion, 1970;Cooper and Jackson, 1972) to 12-24 ductules (Van Wagenen, 1924). This variation is most likely due to differences in the methods used for the determination of ductule numbers.…”

“…Individual rats exhibit large variation in the number of ductules originating from the rete testis (Van Wagenen, 1926;Reid, 1959;Gier and Marion, 1970;Cooper and Jackson, 1972;Dym, 1976;Talo, 1981;Jones and Jurd, 1982;Lewis-Jones, 1982), and some variation in their branching patterns has also been reported (Talo, 1981;Jones and Jurd, 1987).…”

Chemically Induced Sperm Retention Cysts in the Rat

“…1, Fig. 2) and corpus epididymidis, while those in the ductuli efferentes were microscopic (Cooper & Jackson, 1972 Fig. 6.…”

Structure and function of the ductuli efferentes: A review

“…These ductules arise separately from the rete testis near the tunica albuginea. The rete testis in the boar bull, goat, and dog are formed as a central zone within the testis (Hees et al, 1987;Orsi et al, 1983), but in man, rat, mouse, hamster, and bird the rete testis is found a t the testis margin and usually forms an extratesticular portion that connects to the ductuli efferentes (Amann et al, 1977;Budras and Sauer, 1975a;Cooper and Jackson, 1972;Reid and Cleland, 1957).…”