Page 806 - Atlas of Histology with Functional Correlations

through the seminiferous tubules (3, 5), the connective tissue and blood vessels

of the mediastinum testis (10, 16), and the excretory ducts, the ductuli
efferentes (efferent ductules) (9, 13).

A few seminiferous tubules (3, 5) are visible on the left side. The tubules (3,
5) are lined with spermatogenic epithelium and sustentacular Sertoli cells. The
interstitial connective tissue (4) is continuous with the mediastinum testis (10,

16) and contains the steroid (testosterone)-producing interstitial cells (of
Leydig) (1). In the mediastinum testis (10, 16), the seminiferous tubules (3, 5)
terminate in the straight tubules (2, 6) that are short, narrow ducts lined with a
cuboidal or low columnar epithelium that are lined only by Sertoli cells.

The straight tubules (2, 6) continue into the rete testis (7, 8, 12) of the
mediastinum testis (10, 16). The rete testis (7, 8, 12) is an anastomosing network
of tubules with wide lumina lined with a simple cuboidal/low columnar
epithelium. The rete testis (7, 8, 12) widens near the ductuli efferentes (efferent
ductules) (9, 13) into which they empty. The ductuli efferentes (9, 13) are

initially straight but become convoluted in the head of the ductus epididymis.
The ductuli efferentes (9, 13) connect the rete testis (7, 8, 12) to the epididymis
(see Fig. 20.11). Some tubules in the rete testis (12) and ductuli efferentes (9, 13)

contain accumulations of sperm (11, 14).

The epithelium of the ductuli efferentes (9, 13) consists of columnar ciliated
cells that alternate with shorter cuboidal cells with microvilli. Because of the
alternating cell heights, the lining epithelium of the ductuli efferentes appears
uneven.

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