Characteristics of Testicular Spermatozoa and the Fluid which Transports them into the Epididymis

Abstract

Significant advances often depend on the development of a technique, and this applies to the study of testicular spermatozoa. Although spermatozoa could be obtained from the testes of dead animals, the purity of the preparation was questionable, the numbers obtained were insufficient for a critical evaluation of their metabolism, and there was always an uncertainty whether or not spermatozoa collected post mortem were metabolically normal. Most of the work described in this paper stemmed directly from the development of a technique for implanting a catheter (Fig. 1) into the rete testis of rams (99, 102). This technique enabled testicular spermatozoa to be collected in abundant numbers and under physiological conditions in the fluid which carries the spermatozoa out of the testis and into the epididymis. This fluid is unique in many respects. It is the “milieu” which normally bathes the spermatozoa, and probably most of the cells of the germinal epithelium, and so a knowledge of its composition is vital to an understanding of the process of spermatogenesis. Most of this fluid is resorbed selectively in the epididymis so that its composition changes progressively during its passage through the