On the problem of the phagocytic capacity of Sertoli cells. Electron microscopic study in the rat.

To study the real phagocytic capacity of Sertoli cells the following experiments were carried out: carbon colloidal solution or thorium dioxide of particle size 0.01--0.03 micrometer as 2% solution were injected in rat testes at a speed of 50 microliter per minute by means of a infusion pump. The site of injection was made either in the intertubular species under the albuginea or in the lumen of seminiferous tubules using glass 120 micrometer-gauge needles connected to the pump syringe. 30 to 240 minutes after the injection the tissues were fixed by perfusion of 2% glutaraldehyde and embedded for EM. It was observed: 1) particles injected into the intertubular species were not able to pass through the tubular wall and were either trapped by the connective tissue macrophages or drained by the lymphatic vessels; 2) intraluminal particles were not phagocyted by the Sertoli cells and remained in the lumen. The behavior of the Sertoli cells did not match that of phagocytes since they did not show their devouring capacity for the inert particles. These results are consistent with the interpretation that the current disposal of either debris by Sertoli cells depends on autophagic dissolution rather than n macrophagic capacity.

Effect of chronic treatment with prostaglandin E2 on male rat fertility.

Adult male rats were treated with prostaglandin E2 (100 microgram/100 g body wt) during 60 days. Neither morphological alterations in genital organs nor modification in epididymal contractility were observed. Nevertheless, a significant diminution of fertility was registered. This was recovered after 30 days following the cessation of treatment. Since sperm maturation occurs in the epididymis, it is postulated that the decrease of fertility in our experiments was due to an incomplete maturation of germinal cells, induced by a reduction in the time taken by spermatozoa in passing through the duct.

Contractile behaviour of rat epididymis after sympathectomy produced by the administration of guanethidine.

The effect of guanethidine (a sympatholytic agent) on epididymal contractions was studied in rats, in order to contribute new data on the role of both the adrenergic and cholinergic nerves in the spontaneous motility of the epididymis and also during ejaculation. The first type of activity was increased when adrenergic innervation was damaged, but the amplitude and frequency of contractions reached normal values approximately 3 hours after beginning the records. Since spermatozoa were eliminated after electroejaculation, the second type of contractions was not affected either. As the epididymis and vas deferens were congested with spermatozoa, it is possible to assume that guanethidine caused a functional obstruction in a distal segment of the genital tract. The increase of spontaneous activity could be the response of the epididymal muscle to overcome this obstruction and, therefore, to cause the elimination of spermatozoa into the urethra, which normally occurs in absence of ejaculations. Finally, no pregnancies occurred among female rats mated with treated males, at least up to 150 days after ending treatment.

Effects of cyproterone acetate on spontaneous contractility of the rat epididymis.

The spontaneous contractility of the rat epididymis was recorded in vivo and the effects of cyproterone acetate were studied. At 7 days after cyproterone acetate daily administration the records of the epididymal contractility did not show significant differences from the records obtained in control animals. On the contrary, in animals injected during 11 days the amplitude and frequency of epididymal contractions showed a significant decrease, and this activity completely ceased at 14 days of treatment.