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 In this study immunoelectrophoretic and double immunodiffusion analyses were used to investigate the antigenic character of zinc-binding proteins (ZnBPs), whereas the indirect immunofluorescence technique was used to identify their origin in boar reproductive tract. The mmunoelectrophoretic analysis of ZnBPs of the seminal plasma resulted in the appearance of three antigenic protein complexes, while specific immunoreactivity patterns of the anti-ZnBP serum were detected by double immunodiffusion analysis. Indirect immunofluorescence technique confirmed that ZnBPs were secreted by different reproductive tract tissues, suggesting their contributions to the seminal plasma.
Environmental estrogens may be derived from plants (phytoestrogens), pharmaceuticals or synthetic compounds. They exert estrogenic and/or potentially antiestrogenic effects on farm animals, wildlife and humans. Exposure to these compounds results in some abnormalities in the reproductive tract, changes in the estrous cycle, and possibly protection against the development of hormone- dependent cancer. The data obtained from animal studies suggest that the timing of exposure to phytoestrogens is important, and neonatal exposure causes the most pronounced effects.
A thorough understanding of the mechanisms leading to the interaction between the sperm and the ovum in the process of fertilization in birds can facilitate more effective programming and control of the reproduction of these animals in breeding farms. In addition, it may allow the introduction of extracorporeal fertilization techniques, which may be important in the creation of transgenic animals and the reproduction of endangered species. In birds, the process of fertilization is not well known. It is conditioned by a series of interactions between mature reproductive cells. Oocytes are formed in the ovarian follicles of the left ovary. After ovulation, an ovum in the metaphase of the second meiotic division enters the oviduct along with the inner perivitelline layer (IPVL). It gets fertilized in this infundibulum. Male gametes are formed in paired testes located in the abdominal cavity. Sperm cells in the female reproductive tract do not require capacitation and are already fully capable of fertilization. As a result of internal insemination, male reproductive cells enter the oviduct. In this organ, they are selected and stored in the primary and secondary sperm storage tubules of the mucous membrane. They are released in batches shortly before ovulation. After reaching the oocyte, the sperm binds to the IPVL. This induces an acrosomal reaction that allows the male reproductive cells to penetrate to the surface of the oocyte, especially at the germinal pole. Next, as a result of physiological polyspermy, many sperm cells reach the ooplasm where they form haploid male pronucleus. This phenomenon is necessary to activate an polylecithal egg and produce a haploid female pronucleus. In the final stage, the female pronucleus merges with the single male pronucleus, which leads to the formation of a diploid zygote. The excess male pronuclei present in ooplasm are broken down by endonucleases (DNases). Understanding the mechanisms leading to the interaction between sperm and oocyte in birds may allow for more accurate programming and breeding of these animals in poultry farms and the introduction of extracorporeal fertilization techniques. In addition, it could be useful for the reproduction of endangered bird species.
The present study was designed to evaluate the distribution of alpha-naphthyl acetate esterase (ANAE) positive T lymphocytes in the female reproductive tract and ovary throughout the estrous cycle of Angora Goats. Tissue samples were collected on days 5, 10 and 16 of the oestrus cycle and then fixed in formol-sucrose fixative (pH 6.8) and stored for 22 hours at +4°C. The samples were then additionally fixed in Holtz' solution under the same conditions they were in the first fixation. Cryostat sections of 8 µm thickness were stained for alpha naphthly acetate esterase activity at pH 6.4. The ANAE positive T lymphocytes were mainly located in the epithelium, lamina propria and around blood vessels in other region of connective tissues. Density of ANAE positive T lymphocytes in the ovarian and uterine tissues was highest on day 10 and 16 respectively. It was concluded that the estrous cycle may have been responsible for variations in the distribution of ANAE positive T lymphocytes in goat ovarian and reproductive tract tissues.
The study focuses on the activity of alkaline phosphatase, acidic phosphatase and non-specific esterase in the epithelial cells of the oviducts of puerperal ewes with a single lamb (n = 24) and two lambs (n = 24). The experimental animals had the ampullar sections of the oviducts removed on days 7, 17, 25 and 35 postpartum. The results indicated an upward trend in the activity of the investigated enzymes in both groups of animals from day 7 to 35 of the puerperal period. However, the increase in enzyme activity in the ewes with twins was slower in comparison with the ewes with a singleton, which was significantly manifested by lower alkaline phosphatase activity (5.8 ± 0.4 vs 4.3 ± 0.4; P < 0.01), acidic phosphatase activity (11.5 ± 0.3 vs 7.2 ± 0.4; P < 0.05) and non- -specific esterase activity (11.3 ± 0.4 vs 8.7 ± 0.4; P < 0.05) on day 25 postpartum. These differences between the groups persisted until the completion of the experiment with alkaline phosphatase activity (7.1 ± 0.7 vs 5.7 ± 0.3; P < 0.05), acidic phosphatase activity (14.4 ± 0.4 vs 8.6 ± 0.3; P < 0.001) and non-specific esterase activity (11.6 ± 0.5 vs 9.5 ± 0.4; P < 0.01) on day 35 postpartum. The results indicate that the retardation of functional changes in the ewes with twins reveals the prolongation of time essential for the completion of regenerative processes in the epithelium of the oviducts. The discussion deals with the possible utilization of these facts in relation to optimizing out of season breeding in sheep.
Progesterone (P4), which is produced by the corpus luteum (CL), creates proper conditions for the embryo implantation, its development, and ensures proper conditions for the duration of pregnancy. Besides the non-genomic activity of P4 on target cells, its main physiological effect is caused through genomic action by the progesterone nuclear receptor (PGR). This nuclear progesterone receptor occurs in two specific isoforms, PGRA and PGRB. PGRA isoform acts as an inhibitor of transcriptional action of PGRB. The inactive receptor is connected with chaperone proteins and attachment of P4 causes disconnection of chaperones and unveiling of DNA binding domain (DBD). After receptor dimerization in the cells’ nucleus and interaction with hormone response element (HRE), the receptor coactivators are connected and transcription is initiated. The ratio of these isoforms changes during the estrous cycle and reflects the different levels of P4 effect on the reproductive system. Both isoforms, PGRA and PGRB, also show a different response to the P4 receptor antagonist activity. Connection of the antagonist to PGRA can block PGRB, but acting through the PGRB isoform, P4 receptor antagonist may undergo conversion to a strongly receptor agonist. A third isoform, PGRC, has also been revealed. This isoform is the shortest and does not have transcriptional activity. Alternative splicing and insertion of additional exons may lead to the formation of different PGR isoforms. This paper summarizes the available data on the progesterone receptor isoforms and its regulatory action within the female reproductive system.
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