21. Prolactin also appears to be important for spermatogenesis . 22. The GPx4 isoforms mGPx4 and nGPx4 have been implicated in spermatogenesis and male fertility. 23. The encoded protein is expressed at high levels throughout spermatogenesis and in mature sperm. 24. Androgens stimulate inhibin production; this protein may also help to locally regulate spermatogenesis . 25. Inhibin B may be used as a marker of spermatogenesis function and male infertility. 26. Others established a colony that continued to produce new sperm, a process called spermatogenesis . 27. The blood-testis barrier is also important in preventing toxic substances from disrupting spermatogenesis . 28. Excess testosterone evidenced by the beard may indicate mild immunosuppression, which may support spermatogenesis . 29. Spermatogenesis arrests at this stage until puberty.30. ABP is essential to concentrating testosterone in levels high enough to initiate and maintain spermatogenesis .
