Jégou B, Le Magueresse B, Pineau C, Sharpe R M
Groupe d'Etude de la Reproduction chez le mâle (G.E.R.M), URA CNRS 256, Rennes.
Bull Assoc Anat (Nancy). 1991 Mar;75(228):33-8.
Studies in recent years have clearly established that, in addition to the well known endocrine regulation by gonadotrophin hormones, spermatogenesis is under the modulatory control of a complex set of paracrine regulators. Whereas the role of Leydig cells (testosterone) and of Sertoli cells (nurce cells of germ cells) in spermatogenesis has focused most of the attention, until recently little was known about the contribution of germ cells in the spermatogenetic process. This was the aim of the present experiments. We have used, in vitro, 3 complementary approaches; 1) we measured the influence of the removal of germ cells contaminating Sertoli cell cultures by a hypotonic treatment; 2) in coculture, we examined to what extend isolated germ cells could affect Sertoli cell function; 3) we investigated the effects of germ cell conditioned media on Sertoli cell cultures. Our results indicate that germ cells are able to modulate Sertoli cell function in vitro. This germ cell influence varies according to: 1) the germ cell fraction tested (pachytene spermatocytes, early spermatids or cytoplast from elongated spermatids/residual bodies); 2) the parameter of Sertoli cell function studied (inhibition of oestradiol; stimulation of androgen-binding protein, transferrin...); 3) the age of the Sertoli cell donors; 4) the hormonal environment (+/- FSH). Furthermore we wave demonstrated that germ cell effects were partly at least mediated via proteinaceous factor(s) detected in germ cell spent media. Taking into account previous in vivo studies and these in vitro results, we have hypothesized that germ cells, in conjunction with hormones (LH, FSH, testosterone) play an important role in the ontogenesis of Sertoli cells and therefore in spermatogenesis.
近年来的研究已明确证实，除了众所周知的促性腺激素的内分泌调节外，精子发生还受到一组复杂的旁分泌调节因子的调控。虽然睾丸间质细胞（睾酮）和支持细胞（生殖细胞的滋养细胞）在精子发生中的作用最为引人关注，但直到最近，人们对生殖细胞在精子发生过程中的作用仍知之甚少。这就是本实验的目的。我们在体外采用了3种互补的方法：1）我们通过低渗处理测量了去除污染支持细胞培养物的生殖细胞的影响；2）在共培养中，我们研究了分离的生殖细胞在多大程度上能够影响支持细胞的功能；3）我们研究了生殖细胞条件培养基对支持细胞培养物的影响。我们的结果表明，生殖细胞在体外能够调节支持细胞的功能。这种生殖细胞的影响因以下因素而异：1）所测试的生殖细胞部分（粗线期精母细胞、早期精子细胞或来自伸长精子细胞/残余体的细胞质体）；2）所研究的支持细胞功能参数（雌二醇的抑制；雄激素结合蛋白、转铁蛋白的刺激……）；3）支持细胞供体的年龄；4）激素环境（±促卵泡激素）。此外，我们还证明，生殖细胞的作用至少部分是通过在生殖细胞消耗培养基中检测到的蛋白质因子介导的。考虑到先前的体内研究和这些体外结果，我们推测生殖细胞与激素（促黄体生成素、促卵泡激素、睾酮）共同在支持细胞的个体发生中发挥重要作用，因此在精子发生中也发挥重要作用。
