Mammary localization and abundance of laminin, fibronectin, and collagen IV proteins in prepubertal heifers
Mammary localization and abundance of laminin, fibronectin, and collagen IV proteins in prepubertal heifers
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DOI：
10.3168/jds.s0022-0302(03)73883-1
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发表时间：
2003-09-01
影响因子：
3.5
通讯作者：
Akers, RM
中科院分区：
文献类型：
--
作者：
Berry, SDK;Howard, RD;Akers, RM
本研究的目的是确定去卵巢或青春期前小母牛乳腺组织中细胞外基质蛋白纤维连接蛋白、层粘连蛋白和胶原的定位和丰度。取14头6月龄小母牛的乳腺组织和脂肪垫组织，其中8头在1~3个月龄时切除卵巢，6头作为正常对照。组织切片天狼星红染色检测总胶原分布。免疫组织化学方法检测纤维连接蛋白、层粘连蛋白和IV型胶原。Western blotting分析纤维连接蛋白和层粘连蛋白的含量。去卵巢动物的乳房总质量(130+/-21克)要小得多(304+/-25克)。组织学结构不同，完整动物的实质含有丰富、复杂的分枝上皮终末导管单位，而去卵巢动物的终末导管单位大多是主要的导管结构，很少或没有分支。小叶间质中胶原纤维丰富、密集，小叶内间质中胶原纤维较少、弥漫。IV型胶原主要位于成熟导管的基底层，而纤维连接蛋白和层粘连蛋白在正常动物和去卵巢动物的实质间质中均有表达。Western blotting显示，去卵巢小母牛实质内纤维连接蛋白的含量高于脂肪垫，且在实质中的含量显著高于去卵巢小母牛。层粘连蛋白在正常动物的实质中比去卵巢的动物更丰富(30个密度单位/毫克组织比17个密度单位/毫克组织)，但实质和脂肪垫中的层粘连蛋白相似。这些结果提供了纤维连接蛋白、层粘连蛋白和胶原蛋白参与调节小母牛青春期前乳腺发育的初步证据。
The objective was to determine localization and abundance of extracellular matrix proteins fibronectin, laminin, and collagen in mammary tissues from ovariectomized or intact prepubertal heifers. Mammary parenchyma and fat pad tissues were collected from 14 6-mo-old heifers: eight were ovariectomized between 1 to 3 mo of age, and six were used as intact controls. Distribution of total collagen was assessed by Sirius Red staining of tissue sections. Fibronectin, laminin, and type IV collagen were assessed by immunohistochemistry. Abundance of fibronectin and laminin was also analyzed by western blotting. Total mammary mass was much less in ovariectomized animals (130 +/- 21 vs. 304 +/- 25 g). Histological structure differed as parenchyma from intact animals contained abundant, complex branching epithelial terminal ductular units, whereas terminal ductular units from ovariectomized animals were mostly major ductal structures with little or no branching. Collagen fibers were abundant and densely packed throughout interlobular stroma and were less abundant and more diffuse within intralobular stroma. Type IV collagen was primarily in basal lamina of mature ducts, whereas fibronectin and laminin staining were present throughout parenchymal stroma, in both intact and ovariectomized animals. Using western blotting, fibronectin was more abundant within parenchyma than in the fat pad and significantly higher in parenchyma from ovariectomized heifers. Laminin was more abundant in parenchyma from intact than ovariectomized animals (30 vs. 17 densitometric units/mg of tissue), but laminin was similar between parenchyma and fat pad. These results provide initial evidence that fibronectin, laminin, and collagen participate in regulation of heifer prepubertal mammary development.