Regional hypoxia elicits regional changes in chorioallantoic membrane vascular density in alligator but not chicken embryos
Regional hypoxia elicits regional changes in chorioallantoic membrane vascular density in alligator but not chicken embryos
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DOI：
10.1016/s1095-6433(99)00159-2
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发表时间：
2000-01-01
影响因子：
2.3
通讯作者：
Warburton, SJ
中科院分区：
文献类型：
--
作者：
Corona, TB;Warburton, SJ
低氧孵育可增加鸡绒毛膜尿囊膜(CAM)的血管生成。研究了局部低氧对扬子鳄和鸡的血管密度的影响，以确定血管的低氧增殖是局部的还是整体的。鸡蛋在常氧条件下孵化，蛋壳的一部分覆盖无毒的蜂蜡，以诱导外部区域缺氧。用“牛眼”盖片在显微镜下检查凸轮，并测定血管密度指数(VDI)。鳄鱼凸轮的低氧部分比正常氧部分血管更多(VDI值分别为200.9和157.8)。据推测，这种反应是不适应的，因为它导致流向氧合不良部位的血流量增加，即增加了“分流”。因此，我们假设低氧孵育导致的血管增加是由于局部释放和随后快速的局部分解或摄取血管生成因子。相比之下，雏鸡凸轮的低氧和常氧部分的VDI值几乎没有差异(VDI值分别为211.5和217.9)。我们认为，鸡蛋的气室和空气空间允许卵子内气体循环，消除了局部内部缺氧的可能性。(C)2000 Elsevier Science Inc.保留所有权利。
Hypoxic incubation increases vascularization in the chick chorioallantoic membrane (CAM). The effect of regional hypoxia on the vascular density of American alligator (Alligator mississippiensis) and chicken (Gallus gallus) CAMs was studied to determine if hypoxic proliferation of blood vessels is localized or global across the CAM. Eggs were incubated under normoxic conditions with a portion of the eggshell covered with non-toxic beeswax to induce external regional hypoxia. CAMs were examined under a microscope with a 'bulls eye' coverslip and a vascular density index (VDI) was determined. The hypoxic portions of the alligator CAMs were more vascular than the normoxic portions (VDI = 200.9 versus 157.8, respectively). Presumably this response is maladaptive by causing increased blood flow to the poorly oxygenated portions, i.e. increased 'shunt'. Thus, we hypothesize increased vascularity due to hypoxic incubation is due to local release and subsequent rapid local breakdown or uptake of angiogenic factors. In contrast, the hypoxic and normoxic portions of the chick CAMs exhibited virtually no difference in VDI (VDI = 211.5 versus 217.9, respectively). We suggest the air cell and air space of the chicken eggs allows for circulation of gas in ovo, eliminating the possibility of regional internal hypoxia. (C) 2000 Elsevier Science Inc. All rights reserved.