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E. Blesbois and M. de Reviers

Summary. This paper describes the effects of whole seminal plasma and of dialysed seminal plasma on the fertilizing ability of fowl spermatozoa stored for 24 h at 4°C. The fertilizing ability of fowl semen diluted 1:1 with Beltsville Poultry Semen Extender and stored for 24 h at 4°C was enhanced after replacement of the homologous seminal plasma by the diluent (89 versus 77% fertilization rate). Better results were obtained with seminal plasma dialysed against water before sperm storage to discard the < 1 kDa or the < 50 kDa fractions. It was concluded that low molecular weight seminal plasma fractions could damage the fertilizing ability of spermatozoa during storage at 4°C, whereas high molecular weight fractions appeared to enhance fertilizing ability.

Keywords: seminal plasma; fertilizing ability; fowl

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M. LOIR and M. T. HOCHEREAU-DE REVIERS

The ability of nuclear chromatin to bind actinomycin-D appears to be related to the synthesis of RNA (Berlowitz, Pallotta & Sibley, 1968, 1969; Brachet & Hulin, 1970). It has also been suggested that binding of actinomycin-D is associated with physicochemical changes in the deoxyribonucleoproteins (Bolund, 1969; Darzynkiewicz, Gledhill & Ringertz, 1969; Pederson & Robbins, 1970). During spermatogenesis, RNA synthesis ceases before the structure and composition of the nucleoproteins change (Monesi, 1964; Utakoji, 1966; Darzynkiewicz et al., 1969; Gledhill, 1971; Gledhill, Darzynkiewicz & Ringertz, 1971).

Ram germinal cell squashes were fixed in 40% acetic acid and then incubated at 37° C for 15 min in Ringer-phosphate solution containing 0·166 μCi [3H]actinomycin-D/ml (190 mCi/mmol). Unfixed smears of bull germinal cells were incubated in the same solution for 1 hr at 30° C and

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SALLY R. De FAZIO and M. M. KETCHEL

Summary.

Rabbit antibody to human cervical mucus was used in the immuno-electrophoretic analysis of cervical mucus, seminal plasma and blood serum. Eleven antigens were found in cervical mucus, but no more than nine in any one sample. One post-coital sample of cervical mucus in the pool used to produce the antiserum contained an antigen, thought to be prostatic acid phosphatase, derived from the semen contamination. Three antigens appeared specific for cervical mucus, being absent from seminal plasma and serum. Another two antigens were shared with seminal plasma and serum, two were shared with seminal plasma only, and a further two were shared with serum only.

Two of the cervical mucus antigens were identified as immuno-globulin-G and albumin, and another two were believed to be transferrin and α-1 antitrypsin.

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D. Monniaux and M. M. de Reviers

Summary. Iodinated FSH was injected to 18- and 36-day-old rats of 3 strains (03, 04 and 12) with different sensitivity to FSH (12 < 03 < 04) and autoradiography was performed on histological sections of the labelled ovaries. Specific labelling was quantified by microphotometry on histological slides, on granulosa cells of individual follicles with different sizes (> 80 μm diameter) and qualities.

In small preantral follicles (< 160 μm diameter) the labelling was low and homogeneous within the granulosa; it increased between 18 and 36 days of age in the 3 strains. At 36 days, ovaries were characterized by the presence of large preantral and antral follicles with a higher labelling in the outer layers of granulosa (near the theca), compared to the inner layers. In definitely atretic follicles, a loss of binding sites was detected in the outer layers. In rats of Strains 03 and 04, the number of binding sites for FSH in the outer layers of granulosa of follicles with a diameter of > 160 μm increased with follicular size; no change was detected in follicles of Strain 12 rats. The low number of binding sites for FSH and the lack of terminal maturation which characterized the follicles of strain 12 rats can be related to the poor and delayed follicular development, the low sensitivity to exogenous FSH and the low fertility of the animals of this strain.

Keywords: FSH binding; granulosa; follicular growth; rat ovary; quantitative autoradiography; strains of rats

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SALLY R. DE FAZIO and M. M. KETCHEL

Summary.

Extracts of tissues and secretions of women were examined by immunoelectrophoresis with an antiserum against human seminal plasma. Of the twenty-three detected seminal plasma antigens, seven were found in blood serum, and ten antigens not detected in blood serum were found in other female tissues and secretions. Milk was found to contain one non-serum seminal plasma antigen; saliva, urine, vagina and ovary each contained two; cervical mucus and kidney each contained three; nasal secretion, cervix, endometrium, and Fallopian tubes each contained four; and gastric fluid contained five such antigens. It is suggested that women may avoid adverse immunological reactions to seminal plasma because its antigens are not foreign to them.

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D. W. LORDING and D. M. DE KRETSER

Summary.

The interstitial cells of the albino rat testis were studied in animals ranging from the 15th day of fetal life until adulthood. The interstitial cells developed in two phases, a fetal phase from the 17th fetal day to the 2nd postnatal week and an adult phase from the 3rd week onwards. Lipid histochemical and ultrastructural techniques demonstrated the abundance of lipid droplets in the fetal interstitial cells and the paucity of lipid in the adult interstitial cells. The enzyme Δ5-3β-hydroxysteroid dehydrogenase (HSD) was studied in the interstitial cells throughout development using dehydroepiandrosterone (DHEA), pregnenolone and 17α-hydroxy pregnenolone as substrates. The enzyme activity was found with all substrates in both types of interstitial cells, DHEA producing the greatest reaction. The activity of HSD using pregnenolone on substrates was greater in the fetal interstitial cells.

The ultrastructural studies demonstrated the presence of abundant agranular endoplasmic reticulum in both the fetal and adult interstitial cells. The prominent cup-shaped mitochondria and lipid droplets present in the fetal cells were not present in the adult interstitial cells. The differences in the histochemical and ultrastructural features of the cells of each phase suggests that they represent separate generations of interstitial cells.

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G. P. Risbridger and D. M. de Kretser

Summary. The characteristics of the fetal and adult populations of Leydig cells from postnatal rat testes were compared by Percoll gradient centrifugation. A single peak of hCG binding, due to the presence of fetal Leydig cells, was obtained after purification of intertubular cells from 8-day-old animals. Two peaks of specific hCG binding were obtained after purification of intertubular cells from 15-day-old rats: it was confirmed by autoradiographic techniques that the hCG was bound by adult-like Leydig cells in one peak and fetal Leydig cells in the other. Similarly, intertubular cell preparations from 21- and 25-day-old rats resolved into two peaks of hCG binding; adult-like Leydig cells were observed in the first peak, but fetal Leydig cells were rarely observed in the second of these peaks. These results demonstrate the separation of two Leydig cell populations from intertubular cells obtained from animals aged up to 15 days. Thereafter the pattern of the hCG binding profile is similar but is not due to the presence of the same cell types. Therefore these results emphasize the necessity for morphological identification of cell types to permit the correct interpretation of the corresponding biochemical data.

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B. Marquant-Le Guienne and M. De Almeida

Summary. Three autoantigens, S, P and T, have been isolated from epididymal spermatozoa of guinea-pigs. S and P are soluble antigens present on the acrosomal membranes and acrosome matrix. T antigen, a family of several membrane glycoproteins, is distributed over the whole cytoplasmic membrane and on the external acrosomal membrane. Specific antibodies were used to localize the antigens on capacitated and acrosome-reacted spermatozoa and to define their role in acrosome reaction. After capacitation S antigen appeared on the head surface and there was an apparent clustering of T antigen. Both phenomena were prevented by the presence of specific antibodies in the capacitating medium. The acrosome reaction was inhibited both by anti-T and anti-S antibodies as well as by Fab fragments of the same antibodies. The localization of S, P and T antigens on the inner acrosomal membrane after the acrosome reaction suggests that they could also play a role in subsequent steps of fertilization.

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J. B. KERR and D. M. DE KRETSER

Summary.

The formation, distribution and fate of lipid inclusions within the seminiferous tubules of the rat has been studied throughout the spermatogenic cycle. The occurrence of lipid inclusions within the Sertoli cell exhibited cyclic variation with the stages of the rat seminiferous cycle. At stage 9 of the cycle, residual bodies of maturing spermatids were phagocytosed by the Sertoli cell and released numerous lipid droplets which appeared to coalesce into large inclusions at the base of the Sertoli cell at stage 10. The Sertoli cell lipid inclusions persisted throughout the completion of meiosis (stages 11 to 14) and the formation of young spermatids (stages 1 to 2) and their numbers appeared to reach a peak at stages 12 to 13 of the cycle. The inclusions decreased markedly within the Sertoli cell cytoplasm during stage 2 and remained low until stage 9 when lipid from the residual bodies again became available to the cell. This cyclic variation of lipid inclusions within the Sertoli cell does not support previously held views that there is a gradual decline in Sertoli cell lipid during stages 10 to 14 of the spermatogenic cycle. A hitherto unnoticed finding was the presence of large lipid inclusions in the cytoplasm of late pachytene to diakinetic spermatocytes, and some observations suggest a transfer of these lipid inclusions from the Sertoli cells to primary spermatocytes.

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M. De Silva and J. J. Reeves

Summary. Indomethacin or saline was administered via intramuscular, intrauterine or intraovarian routes to dairy cows, within 24 h after standing oestrus was first observed. The incidence of ovulation was determined at slaughter. All of the saline-treated cows (18/18) ovulated. Ovulation was not blocked after intramuscular injection (0/6) or intrauterine infusion (0/6) of indomethacin. In all cows, ovulation was blocked after intraovarian injection (6/6) of indomethacin. These findings add support to the hypothesis that prostaglandins play an essential role in ovulation in the cow as in many other mammalian species.