The fine structure of developing unit collagenous fibrils in the chick.
The fine structure of developing unit collagenous fibrils in the chick.
复制标题
雏鸡中正在发育的单位胶原原纤维的精细结构。
DOI：
10.1002/aja.1001400209
复制
发表时间：
1974
期刊：
影响因子：
--
通讯作者：
F. N. Low
中科院分区：
文献类型：
--
作者：
D. Morse;F. N. Low
椎周宫颈结缔组织取自孵化期从 72 小时到孵化的鸡胚以及 4、8、12 和 16 周龄的雏鸡。除了用 5% 乙酸双氧铀水溶液整体染色外，电子显微镜的准备工作是常规的。薄片的胶原酶消化证实带状细胞外原纤维中存在原胶原。
大约 7 天后，原纤维中的条带变得明显，但无法测量重复单元。靠近结缔组织细胞的带状材料以宽片形式存在。与微原纤维物理相关的部分带状原纤维（250埃宽）存在于无细胞区域。原纤维直径在第二周增长缓慢（最高 300 A），但在第 14 和 15 天增加近 200 A。在加速生长期后，大于 500 A 的原纤维可抵抗铀和铅染色。较小的原纤维 (< 500 A) 仍能很好地染色。可测量周期性的基本条带模式在第八天建立。它由一个主双峰、两个小双峰和两个单峰组成。期内距离不会随着生长而发生显着变化（平均 510 A）。基本图案的第一个小双峰和单峰附近的附加带在第 14 和 15 天时首先清晰可见。条带和周期长度的模糊性被认为是由于截面平面、其他原纤维和片状无定形材料对细节的干扰或可能是由于沿单个原纤维长度的不同收缩造成的。
Perivertebral cervical connective tissue was taken from chick embryos of incubation ages from 72 hours through hatching and from 4, 8, 12, and 16 week old chicks. Preparations for electron microscopy were routine except for en bloc staining with 5% aqueous uranyl acetate. Collagenase digestions of thin sections confirmed the presence of tropocollagen in banded extracellular fibrils.
Banding becomes demonstrable in fibrils at about seven days but repeating units cannot be measured. Close to connective tissue cells the banded material is present in wide sheets. Partially banded fibrils (250 A wide) physically related to microfibrils are present in acellular regions. Growth in fibril diameter is slow through the second week (up to 300 A) but increases nearly 200 A on days 14 and 15. Fibrils larger than 500 A resist uranium and lead staining following the period of accelerated growth. Smaller fibrils (< 500 A) continue to stain well. A basic banding pattern of measurable periodicity is established by the eighth day. This consists of a major doublet, two minor doublets, and two singlets. The intraperiod distance does not change significantly with growth (510 A average). Additional bands near the first minor doublet and singlets of the basic pattern are first clearly demonstrable at 14 and 15 days. Ambiguities in banding and period length are believed to be due to plane of section, interference with detail by other fibrils and flaky amorphous material or possibly to differential shrinkage along the length of a single fibril.