The Role of Oviduct in a Reproduction

Summary: Oviduct constitutes environment for sperm capacitation, fertilization, preimplantation embryo development, gamete and embryo transport. Its wall is built by serous membrane, smooth muscles and mucosa, covered with pseudostratified epithelium, with ciliated, secretory and basal cells. Ciliated cells enhance gamete and embryo transfer in the oviduct. Secretory cells produce and release specific glycoproteins. Basal cells continuously renew the population of epithelial cells. The mucous membrane is subject to cyclic transformations secondary to changes in hormonal profiles during menstrual cycle. Eight morphological phases were identifiedn: 1. preciliogenic, 2. ciliogenic, 3. phase of ciliation with majority of ciliating cells over ciliated, 4. phase of ciliation with majority of ciliated cells over ciliating, 5. phase of ciliated cells with secretory cells activity, 6. phase of early regression, 7. late regression, 8. complete regression. Important role in reproduction plays also oviductal fluid consisting of epithelial cells discharge, peritoneal fluid and blood vessels filtrate. Its composition and quantity is sex hormone dependent. Mucosa and muscles play role in transportation of gametes and emryo. The transport depends on ciliated cells and smooth muscle contractions secondary to stimulation of alpha and beta receptors. The quantity of the receptors depends on oestrogen and progesterone levels.

Key words:oviduct, reproduction.

Epididymal Hormone

Summary: Spermatozoa leaving the testis are immature. They undergo numerous morphological, biochemical and functional changes during passage through the epididymis, where they acquire the ability for progressive motility, survival in male and female tracts, the ability to capacitation, the acrosome reaction and fertilization. The specific microenvironment for sperm maturation and the maintenance of sperm viability is formed by epididymal epithelial cells. The cells synthesize and release into the lumen of epididymis proteins, glycoproteins, glycolipids, phospholipids essential for the maturation and storage of spermatozoa. The secretion and reabsorption in epididymal epithelial cells is androgen-dependent. However, epididymal epithelial cells of rat in vitro reveal also intrinsic steroidogenic activity. They synthesize androgens, that are aromatized to 17b-estradiol. Additionally, they are the source of propiomelanocortin, proenkephalin and oxytocin. Therefore, the epididymis should be seen additionally as a peripheral endocrine organ.

Key words: epididymal epithelial cells, hormones, hormone receptors

Application of Flow Cytometry to Evaluate of Human Sperm DNA Condensation and Integrity

Summary: Many cases of male infertility are of genetic and molecular nature which may lead to morphological and functional disorders of spermatozoa. Both the development and application of Assisted Reproductive Techniques, particularly Intracytoplasmic Sperm Injection (ICSI), may produce a risk of injecting a spermatozoon with damaged DNA (e.g. abnormal condensation and strand breaks) into ovum which in turn may threaten conception or contribute to an early abortion. The present review provides an overview of two assays (Sperm Chromatin Structure  and TUNEL Assay) in which flow cytometry is applied to detect early condensation and integrity abnormalities of DNA in large number of spermatozoa. These assays are of considerable predictive value for in vivo and in vitro fertilization.

Key words: spermatozoa, DNA condensation, DNA strand breaks, flow cytometry, apoptosis, ultrastrukture

Role of  Prolactin in Male Reproductive System

Summary: Prolactin (PRL), the protein hormone of molecular weight of approximately 23kD is synthesized mainly by the cells of adenohypophysis. However, other cells are capable of producing this hormone too. Pituitary lactotrophs demonstrate morphological and functional sex dependent heterogeneity and synthesized PRL undergoes variable posttranslational modifications. Prolactin and its structural variants can influence many biological processes and secretion of this hormone is controlled by numerous releasing and inhibiting factors. In the male reproductive system PRL affects not only the morphology and function of testis, but also epididymis, seminal vesicles, prostate and spermatozoa. Prolactin may act directly through its receptors localized within these organs and indirectly through regulation of gonadotropins liberation from the pituitary gland or testosterone secretion from the testis. The structure and localization of prolactin receptors in the male reproductive tract were discussed in the study. The effect of this hormone following hyperprolactinemia was also determined in the organs mentioned above. Unlike the effect of PRL on the female reproductive system, which is well established and determined, the influence of this hormone on the male reproductive system has not been fully investigated and further studies in this area are required.

Key words: prolactin, testis, epididymis, spermatozoa, seminal vesicles, prostate, prolactin receptors, hyperprolactinemia