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MANNFRED A. HOLLINGER and JOSEPH R. DAVIS

Summary.

The catabolic fate of [U-14C]d-glucose has been studied under aerobic conditions of incubation in slices of mature scrotal, immature abdominal and experimentally-induced cryptorchid testes of the rat. In comparison with the mature scrotal testis, CO2 production in the cryptorchid and the immature testis was found to be decreased by 45 and 55%, respectively. In contrast, protein labelling from radio-active glucose was found to be increased in the cryptorchid and the immature testis by a factor of 4·6 and 13·4, respectively. Successive ion-exchange chromatography of the perchloric acid-soluble fraction of the mature scrotal testis resulted in the elution of thirteen peaks of radio-activity from an anionic resin and five peaks of radio-activity from a cationic resin. The major catabolites occurring in slices of the mature scrotal testis were lactate, aspartate, glutamate, glutamine and α-ketoglutarate, accounting for 93% of the total perchloric acid-soluble radio-activity of glucose. Lactic acid accounted for 45·5, 36·9 and 15·9% in the mature scrotal, cryptorchid and immature testis, respectively. An additional unknown peak of radio-activity not found in samples of the mature scrotal testis was eluted from samples of both the immature abdominal and the experimentally-induced cryptorchid testis. It is suggested that of the cells of the seminiferous germinal epithelium, the maturing spermatids are characterized by the highest rate of glucose utilization into acid-soluble catabolites with a marked reduction in glucose catabolism occurring in the spermatogonia and primary spermatocytes.

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ADRIANA SEILICOVICH and ANÍBAL PÉREZ LLORET

Summary.

Cytochemical studies were carried out on normal and cryptorchid human testes in order to define the distribution of glycogen and some related enzymes during testicular maturation. The glycogen content, and phosphorylase and amylo 1-4,1-6 transglucosidase activities increased in the seminiferous tubules of scrotal testes with maturation. Weaker reactions were always obtained in cryptorchid testes. Phosphorylase and amylo 1-4,1-6 transglucosidase activities were detected in some cells in the intertubular spaces. The localization of these enzymes in scrotal and cryptorchid testes differed at different ages. It was not possible to demonstrate the presence of glycogen synthetase. The rôle played by these glycogen metabolism enzymes in the testis is discussed.

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S. WIERZBOWSKI and E. WIERZCHOS

White, Larsen & Wales (1959) obtained semen from the epididymis of the ram by establishing a fistula into the vas deferens. This method enabled the authors to make observations on epididymal semen without contamination by other accessory gland secretions and allowed them to carry out comparative studies on normally ejaculated spermatozoa. The technique was subsequently improved by Ewy & Bielański (1962). Bennett & Rowson (1963) developed a technique for cannulating the vas deferens in the bull, which was modified by Amann, Hokanson & Almquist (1963) and used in further studies on the output of spermatozoa in the ram by Bielański & Ewy (1966), Tischner (1966, 1967) and Zełtobriuch, Łoginowa & Manuiłow (1966). This communication describes a technique for cannulation of the vas deferens in the boar. Three Landrace boars were used. Their ages
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S. R. BAWA, KULDIP C. KANWAR and PAWAN K. SINGAL

It is well known that rigs or cryptorchids with abdominal testes are sterile (Crewe, 1922; Nordby, 1928). Further, in unilateral cryptorchidism, clinical as well as experimental, normal functioning of the abdominal testis is impaired; the nature of the damage is similar to that described for the bilaterally cryptorchid testis (see Kormano, Härkönen & Kontinen, 1964).

Though testicular histology in response to hyperthermia has recently been investigated, biochemical, histochemical and cytochemical studies on the mammalian testis subjected to hyperthermia are few (see Collins & Lacy, 1969). No attempt has yet been made to study both testes from the same animal, where one is maintained at normal temperature and the other testis is subjected to heat. Comparative studies on normal and heat-treated testes from the same animal would supply direct information on whether the effects produced are

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M. A. HOLLINGER and J. R. DAVIS

Previous data from this laboratory have indicated that the change in protein labelling of slices of experimentally-induced cryptorchid rat testes and testes from rats fed nitrofurazone is similar in that the incorporation of l-lysine-U-14C progressively increases during both experimental periods (Davis, Morris & Hollinger, 1964; Hollinger & Davis, 1966). More recent data from this laboratory have indicated that while there is a reduced capacity to catabolize d-glucose-U-14C into acid-soluble intermediates, protein labelling from radio-active glucose is markedly elevated in the cryptorchid testis (Hollinger & Davis, 1968). The atrophic changes in the testis of the nitrofuran-treated rat closely resemble those in the experimentally-induced cryptorchid rat testis in that both testes show an absence of spermatids and mature spermatozoa. It seemed of interest, therefore, to study the glucose metabolism
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PARTHASANKAR RAY and AMAR CHATTERJEE

The deleterious effect of cadmium on the testis has been ascribed to failure of regulation of the testicular temperature by the pampiniform plexus (Turner, 1966) and cadmium-induced damage to the capillary endothelium (Maekawa, Tsunenari & Kurematsu, 1966; Gunn, Gould & Anderson, 1963). Our recent findings in the rat of an early differential effect of cadmium on the scrotal and contralateral cryptorchid testes in the same individual do not entirely support the theory implicating the pampiniform plexus as the site of cadmium action (Chatterjee & Ray, 1972). The higher rate of incorporation of tritiated lysine in a cryptorchid testis compared to its scrotal counterpart (Davis, 1965) suggests that the abdominal temperature may cause an initial heat-induced vasodilatation of the spermatic vasculature and thereby augment the blood flow through the cryptorchid testis (Glover, 1965). This paper describes our findings concerning the effect of reserpine or adrenalectomy in preventing an early detrimental and

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J. M. Johnson and L. C. Ellis

Summary. PG synthetase activity was assessed histochemically in the reproductive tract of male rats. Moderate activity was observed in tails of spermatozoa within the corpus and cauda epididymidis but there was no activity in the caput epididymidis or the seminiferous tubules. The sperm tail activity was maximal for cells within the vas deferens. PG synthetase activity was also observed in individual adipose cells adhering to the testicular capsule, epididymis and vas deferens, and in isolated interstitial cells of the testis and the caput, corpus and cauda epididymidis. Specific cells in the capsules of the testes, epididymis and vas deferens also produced PGs. The activity observed in the interstitial cells of the testis and the caput epididymidis was less than that for the other tissues in terms of the proportion of possible cells. The demonstration of PG synthetase activity paralleled the known loss of arachidonic acid from the phospholipids of the spermatozoa as they pass through the male tract. Endogenous substrate was not limiting in the assay system, even in the testis and caput epididymidis where PG synthesis was not normally observed, indicating that a PG synthesis inhibitor may be present in these two tissues. PG synthetase activity within teased seminiferous tubules was markedly increased by physical trauma. Indomethacin diminished but did not eliminate synthesis.

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Ch. Jean-Faucher, M. Berger, C. Gallon, M. de Turckheim, G. Veyssiere and Cl. Jean

Summary. The concentrations of testosterone and dihydrotestosterone (DHT) were measured in the testis and in different segments of the epididymis and vas deferens of adult mice. There were marked regional variations in the concentrations of testosterone and DHT from the testis to the caudal part of the vas deferens. In the testis, testosterone was the predominant androgen (364 ± 90 ng/g) while DHT was weakly represented (8 ± 2 ng/g). Qualitative and quantitative changes occurred in epididymis: DHT was the main steroid in the caput (29·3 ± 2·7 ng/g) and corpus (33·1 ± 4·4 ng/g) while testosterone and DHT were in similar quantities in the cauda (18·6 ± 2·6 and 19·0 ± 2·7 ng/g, respectively). The proximal region of the vas deferens contained higher amounts (71·4 ± 8·0ng/g) of androgens (testosterone + DHT) than did the caput epididymidis (39·1 ± 3·3 ng/g). Testosterone was the predominant androgen in each part of the vas deferens and its concentrations decreased from the proximal (64·5 ± 7·5 ng/g) to the caudal (26·9 ± 4·3 ng/g) region. Castration and section of the efferent ducts of the testis showed that the epididymis received testosterone essentially via the blood supply and that epididymal DHT was produced locally from circulating testosterone.

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Nina Atanassova, Chris McKinnell, Jane Fisher and Richard M Sharpe

This study investigated whether transient, neonatal (days 2–12) treatment of rats with the potent oestrogen, diethylstilboestrol (DES), altered the structure of the cauda epididymis/vas deferens in adulthood, and if the changes observed related to altered development of basal cells in early puberty. Neonatal treatment with 10 μg DES resulted in the following during adulthood: (a) coiling of the normally straight initial vas deferens, (b) gross epithelial abnormalities, (c) 4-fold widening of the periductal non-muscle layer, (d) infiltration of immune cells across the epithelium into the lumen, and (e) reduction/absence of sperm from the vas deferens lumen. Amongst affected animals >75% exhibited reduced epithelial immunoexpression of androgen receptor and aberrant oestrogen receptor-α immunoexpression and 63% exhibited multi-layering of basal cells coincident with increased epithelial cell proliferation. None of the aforementioned changes occurred in rats treated neonatally with 0.1 μg DES.

As basal cells play a key role in the development of epithelia such as that in the epididymis and vas deferens, we went on to investigate if neonatal DES treatment affected basal cell development. In controls, basal cells were first evident at day 10 (vas deferens) or day 18 (cauda). Rats treated with 10 μg, but not those treated with 0.1 μg, DES, showed ~90% reduction (P < 0.001) in basal cell numbers at day 15 and day 18. This decrease coincided with gross suppression of testosterone levels; co-treatment of rats with 10 μg DES + testosterone maintained basal cell numbers at control levels at day 18. However, suppression of testosterone production (GnRH antagonist treatment) or action (flutamide treatment) did not alter basal cell numbers. It is concluded that neonatal exposure to high oestrogen levels coincident with reduced testosterone action results in abnormal changes in the adult cauda/vas deferens that are preceded by delayed differentiation of basal cells. These findings imply a role for androgens and oestrogens in basal cell development and suggest that this may be pivotal in determining normal epithelial (and stromal) development of the cauda/vas deferens.

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Rukmali Wijayarathna, David M de Kretser, Rajini Sreenivasan, Helen Ludlow, Ralf Middendorff, Andreas Meinhardt, Kate L Loveland and Mark P Hedger

Activin A regulates testicular and epididymal development, but the role of activin B in the epididymis and vas deferens is unknown. Mouse models with reduced activin A (Inhba +/− and Inhba BK/+), or its complete absence (Inhba BK/BK), were investigated to identify specific roles of activins in the male reproductive tract. In 8-week-old Inhba +/− mice, serum activin A decreased by 70%, with a 50% reduction of gene expression and protein in the testis, epididymis and vas deferens. Activin B and the activin-binding protein, follistatin, were similar to wild-type. Testis weights were slightly reduced in Inhba +/− mice, but the epididymis and vas deferens were normal, while the mice were fertile. Activin A was decreased by 70% in the serum, testis, epididymis and vas deferens of Inhba BK/+ mice and was undetectable in Inhba BK/BK mice, but activin B and follistatin levels were similar to wild-type. In 6-week-old Inhba BK/BK mice, testis weights were 60% lower and epididymal weights were 50% lower than in either Inhba BK/+ or wild-type mice. The cauda epididymal epithelium showed infoldings and less intra-luminal sperm, similar to 3.5-week-old wild-type mice, but at 8 weeks, no structural differences in the testis or epididymis were noted between Inhba BK/BK and wild-type mice. Thus, Inhbb can compensate for Inhba in regulating epididymal morphology, although testis and epididymal maturation is delayed in mice lacking Inhba. Crucially, reduction or absence of activin A, at least in the presence of normal activin B levels, does not lead to major defects in the adult epididymis or vas deferens.