Intra-Testicular Signals Regulate Germ Cell Progression and Production of Qualitatively Mature Spermatozoa in Vertebrates

Intra-Testicular Signals Regulate Germ Cell Progression and Production of Qualitatively Mature Spermatozoa in Vertebrates

Spermatogenesis, a highly conserved process in vertebrates, is mainly under the hypothalamic-pituitary control, being regulated by the secretion of pituitary gonadotropins, follicle stimulating hormone, and luteinizing hormone, in response to stimulation exerted by gonadotropin releasing hormone from hypothalamic neurons. At testicular level, gonadotropins bind specific receptors located on the...

Cytogenetics of the progression of adult testicular germ cell tumors.

genetics of testicular germ cell tumors

testicular germ cell tumor (tgct) is the most solid tumor in 20-40 years old man. tgct account for 95% of testicular tumors and represent a unique type of human cancer from several different perspectives. tgct arise by transformation of germ cells. the transformed germ cells exhibit ploripotentially to differentiate into embryonic. extra-embryonic, and somatic tissue types, and are highly sensi...

I-5: Multicellular Human Testicular Organoid: A Novel 3D In Vitro Germ Cell and Testicular Toxicity Model

Background Background: Mammalian spermatogenesis is regulated through paracrine and endocrine activity, specific cell signaling, and local control mechanisms. These highly specific signaling interactions are effectively absent upon placing testicular cells into two-dimensional primary culture. The specific changes that occur between key cell types and involved spermatogenesis signaling pathways...

Intrinsic signals regulate the initial steps of myogenesis in vertebrates.

In vertebrates, despite the evidence that extrinsic factors induce myogenesis in naive mesoderm, other experiments argue that the initiation of the myogenic program may take place independent of these factors. To resolve this discrepancy, we have re-addressed this issue, using short-term in vivo microsurgery and culture experiments in chick. Our results show that the initial expression of the m...