Rheological and physiological consequences of conversion of the maternal spiral arteries for uteroplacental blood flow during human pregnancy.
Rheological and physiological consequences of conversion of the maternal spiral arteries for uteroplacental blood flow during human pregnancy.
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DOI：
10.1016/j.placenta.2009.02.009
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发表时间：
2009-06
期刊：
影响因子：
3.8
通讯作者：
Kingdom, J. C. P.
中科院分区：
文献类型：
--
作者：
Burton, G. J.;Woods, A. W.;Jauniaux, E.;Kingdom, J. C. P.
母体螺旋动脉的生理转换是人类成功怀孕的关键。它涉及平滑肌和弹性膜从血管壁的损失，直到子宫肌层的内三分之一，并与血管口处的5-10倍扩张有关。转复失败伴随着常见的妊娠并发症，如早发型先兆子痫和胎儿生长受限。在这里，我们使用来自三维重建的文献中的尺寸，模拟终末扩张对足月胎盘绒毛间隙血液流入的影响。我们观察到，扩张将0.4-0.5 mm直径的动脉的非扩张部分中的流速从2 m/s减慢到3 m/s，在2.5 mm直径的口处减慢到约10 cm/s，这取决于确切的半径和粘度。该速率预测通过绒毛间隙的传输时间约为25秒，与观察到的时间密切匹配。该模型表明，在没有转化的情况下，血液将以1-2 m/s的速率作为湍流射流进入绒毛间隙。我们推测高动量会破坏绒毛结构，破坏锚定绒毛，并产生超声证实的回声囊性病变。平滑肌的保留也会增加自发性血管收缩和缺血再灌注损伤的风险，产生氧化应激。扩张对总血流量的影响令人惊讶地温和，因此我们认为与转换不足相关的胎盘病理学主要是由流变学后果而不是慢性缺氧所主导。
Physiological conversion of the maternal spiral arteries is key to a successful human pregnancy. It involves loss of smooth muscle and the elastic lamina from the vessel wall as far as the inner third of the myometrium, and is associated with a 5–10-fold dilation at the vessel mouth. Failure of conversion accompanies common complications of pregnancy, such as early-onset preeclampsia and fetal growth restriction. Here, we model the effects of terminal dilation on inflow of blood into the placental intervillous space at term, using dimensions in the literature derived from three-dimensional reconstructions. We observe that dilation slows the rate of flow from 2 to 3 m/s in the non-dilated part of an artery of 0.4–0.5 mm diameter to approximately 10 cm/s at the 2.5 mm diameter mouth, depending on the exact radius and viscosity. This rate predicts a transit time through the intervillous space of approximately 25 s, which matches observed times closely. The model shows that in the absence of conversion blood will enter the intervillous space as a turbulent jet at rates of 1–2 m/s. We speculate that the high momentum will damage villous architecture, rupturing anchoring villi and creating echogenic cystic lesions as evidenced by ultrasound. The retention of smooth muscle will also increase the risk of spontaneous vasoconstriction and ischaemia–reperfusion injury, generating oxidative stress. Dilation has a surprisingly modest impact on total blood flow, and so we suggest the placental pathology associated with deficient conversion is dominated by rheological consequences rather than chronic hypoxia.
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DOI：
10.1111/j.1471-0528.1981.tb02222.x
发表时间：
1981-01-01
期刊：
BRITISH JOURNAL OF OBSTETRICS AND GYNAECOLOGY
影响因子：
--
作者：
GERRETSEN, G;HUISJES, HJ;ELEMA, JD
通讯作者：
ELEMA, JD
DOI：
10.1016/s0002-9378(87)80354-x
发表时间：
1987-07-01
影响因子：
9.8
作者：
BLOXAM, DL;BULLEN, BE;LAO, TT
通讯作者：
LAO, TT
影响因子：
0.9
作者：
Hsieh, YY;Chang, CC;Tsai, CH
通讯作者：
Tsai, CH
影响因子：
3.8
作者：
Aardema, MW;Oosterhof, H;Aarnoudse, JG
通讯作者：
Aarnoudse, JG
DOI：
10.1016/s0950-3536(87)80024-0
发表时间：
1987-09-01
期刊：
Bailliere's clinical haematology
影响因子：
--
作者：
Heilmann, L
通讯作者：
Heilmann, L