Fröjdman K, Pelliniemi L J, Virtanen I
Department of Anatomy, University of Helsinki, Finland.
Differentiation. 1998 Jul;63(3):125-30. doi: 10.1046/j.1432-0436.1998.6330125.x.
The localization of type IV collagen alpha 1-alpha 5 chains in the differentiating rat testis and ovary was studied by immunocytochemistry. The initial formation of the testis and ovary included the appearance of collagen alpha 1/alpha 2(IV) chains in the gonadal blastemas. Upon further differentiation of the epithelia of the gonads alpha 1/alpha 2(IV) chains became localized in all of the respective basement membranes (BMs). The alpha 3, alpha 4 and alpha 5 chains of type IV collagen were not detectable in the prenatal rat testis and ovary. With the postnatal differentiation of the rat testis the alpha 3-alpha 5(IV) chains gradually appeared, and were localized in BMs of the testicular cords and seminiferous tubules, rete cords, myoid cells, surface epithelium, Leydig cells, and in some blood vessels. In the postnatal rat ovary, the alpha 3(IV) chain appeared in the BMs of small cortical follicles whereas the BMs of secondary and more deeply localized follicles were devoid of this chain. The alpha 1/alpha 2(IV) chains were abundant in the theca. A reaction for alpha 3-alpha 5(IV) chains also appeared in the BM of the ovarian surface epithelium and of some blood vessels after birth. The present results show that the alpha 3-alpha 5(IV) chains are not only less widely distributed than the alpha 1/alpha 2(IV) chains but are also synthesized much later in development. The late appearance of the alpha 3-alpha 5(IV) chains shows that the development of the mature testicular and ovarian BMs is a long process and that the time schedule for the synthesis of these chains is different from that of many other extracellular matrix proteins. A careful analysis of the expression of alpha 3(IV) chain may be useful in the further study of the kinetics and regulation of ovarian follicular growth.
通过免疫细胞化学方法研究了IV型胶原α1-α5链在大鼠睾丸和卵巢分化过程中的定位。睾丸和卵巢的初始形成包括性腺母细胞中胶原α1/α2(IV)链的出现。随着性腺上皮的进一步分化，α1/α2(IV)链定位于所有相应的基底膜（BMs）中。在产前大鼠的睾丸和卵巢中未检测到IV型胶原的α3、α4和α5链。随着大鼠睾丸的出生后分化，α3-α5(IV)链逐渐出现，并定位于睾丸索、生精小管、网索、肌样细胞、表面上皮、Leydig细胞以及一些血管的基底膜中。在出生后的大鼠卵巢中，α3(IV)链出现在小皮质卵泡的基底膜中，而次级卵泡和更深层定位卵泡的基底膜中则没有该链。α1/α2(IV)链在卵泡膜中丰富。出生后，α3-α5(IV)链的反应也出现在卵巢表面上皮和一些血管的基底膜中。目前的结果表明，α3-α5(IV)链不仅分布不如α1/α2(IV)链广泛，而且在发育过程中合成也晚得多。α3-α5(IV)链的晚期出现表明成熟睾丸和卵巢基底膜的发育是一个漫长的过程，并且这些链的合成时间表与许多其他细胞外基质蛋白不同。对α3(IV)链表达的仔细分析可能有助于进一步研究卵巢卵泡生长的动力学和调节。
