It is well established in various experimental models that luteinizing hormone (LH) stimulated testosterone (T) production of Leydig cells is the key endocrine stimulus of spermatogenesis. The role of the other gonadotrophin, follicle-stimulating hormone (FSH), is as yet somewhat unclear given that several clinical conditions and experimental models, including men with inactivating FSH receptor...

Signaling through vitamin A metabolites is indispensable for spermatogenesis, and disruption of retinoic acid receptor alpha (RARalpha) function resulted in male sterility and aberrant spermatogenesis, which resembled vitamin A deficiency. Here we investigated the lineage- and cell-specific role of RARalpha-mediated signaling during spermatogenesis using germ-cell transplantation and geneticall...

Spermatogenesis is a dynamic developmental process requiring precisely timed transitions between discrete stages. Specifically, the germline undergoes three transitions: from mitotic spermatogonia to spermatocytes, from meiotic spermatocytes to spermatids, and from morphogenetic spermatids to spermatozoa. The somatic cells of the testis provide essential support to the germline throughout sperm...

Abstract The Chinese soft‐shelled turtle ( Pelodiscus sinensis ) is a reptile that undergoes seasonal reproduction. To produce enough spermatozoa during the mating season, immature can be quickly released from testis. Cell morphological changes related to maturation process are then completed in epididymis. In this way, develop simultaneously epithelium and lumen of seminiferous tubules, making...

Mapping epigenetic modifications and identifying their roles in the regulation of spermatogenesis and embryogenesis are essential for gaining fundamental medical understandings and for clinical applications. More and more evidence has shown that specific epigenetic modifications are established during spermatogenesis, which will be transferred into oocyte via fertilisation, and play an importan...

Spermatogenesis in the charophyte Nitella has been followed in antheridia prepared for light and electron microscopy. The antheridial filament cells contain paired centrioles which are similar in structure and behavior to the centrioles of animal cells. In the early spermatid, the centrioles undergo an initial elongation at their distal ends and become joined by a spindle-shaped fibrous connect...

background: nanoparticles have wide range of application while there are some reports regarding their probable effects on male reproductive system and spermatozoa. objective:  the aim of this study was to evaluate the effect of different doses of silver nanoparticles (agnps) (70nm) on acrosome of rat spermatozoa and number of spermatogenic cells. materials and methods:  in this experimental stu...

conclusions the results of the present study indicate the protective effects of melissa officinalis on some sperm parameters and spermatogenesis quality in rats exposed to lead. background some medicinal plants with their antioxidant properties have protective effects on sperm parameters and neutralize the harmful effects of lead exposure. objectives the present study aimed to determine the eff...

background: advancement in the treatment of various types of cancer has led to greater patient survival. these treatments essentially have toxic effects on different kinds of cells, such as germ cells. infertility as one of the side effects of cancer treatment has changed the quality of life of young cancer survivors dramatically. melatonin is an antioxidant with receptors in the reproductive s...

objective: evaluation of the effects of toxoplasma gondii infection on spermatogenesis in male rats. materials and methods: the rh strain of t. gondii tachyzoites were injected interaperitoneally in an infected group of 35 rats, while 21 rats were used as controls. each ten days from 10- 70 days of post-infection (pi), 5 rats from infected group and 3 rats from control group were scarified. t...