Increased ocular blood vessel numbers and sizes following chronic sympathectomy in rat
Increased ocular blood vessel numbers and sizes following chronic sympathectomy in rat
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DOI：
10.1006/exer.2002.1182
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发表时间：
2002-06-01
影响因子：
3.4
通讯作者：
Smith, PG
中科院分区：
文献类型：
--
作者：
Steinle, JJ;Pierce, JD;Smith, PG
以眼血管病理为特征的疾病状态通常与交感神经功能受损相关。本研究探讨了交感神经切断对成年大鼠眼血管的影响。葡萄膜灌注和脉络膜和视网膜血管的大小和数量进行了评估，在大鼠与完整的神经支配，并在短期（2天）或长期（6周）交感神经去神经诱导同侧上级颈神经节切除。在神经支配完整的大鼠中，经过短期交感神经切除术后，双眼的血流量相当。然而，经过长期的交感神经切除术，血流是四倍以上，在神经支配的眼睛，但泪腺，大脑皮层和咬肌不变。脉络膜表面积不受长期交感神经切除术的影响，但脉络膜厚度增加，血管腔所占的脉络膜横截面积更大。脉络膜单位横截面积上的小动脉数目没有改变，但小动脉直径增大。脉络膜小静脉更大，更丰富。脉络膜毛细血管数量不变，但外丛状层的视网膜毛细血管增加。为了确定这些变化是否由交感神经活动的丧失引起，慢性切除交感神经节前神经支配。这导致脉络膜厚度和血管腔面积以及外丛状层中的小动脉、小静脉和毛细血管的数量显著增加。这些发现表明，交感神经支配在调节脉络膜和视网膜血管分布中是至关重要的，并且交感神经活性的慢性丧失可能导致诸如年龄相关性黄斑变性和糖尿病视网膜病变等疾病中的异常血管增殖。(C)2002 Elsevier Science Ltd.
Disease states characterized by ocular vascular pathology are often associated with impaired sympathetic function. This study examined the effect of sympathetic denervation on ocular vasculature of the adult rat. Uveal perfusion and choroidal and retinal blood vessel sizes and numbers were assessed in rats with intact innervation and after short- (2 days) or long-term (6 weeks) sympathetic denervation induced by ipsilateral superior cervical ganglion excision. In rats with intact innervation and after short-term sympathectomy, blood flow in both eyes was comparable. However, after long-term sympathectomy, blood flow was four-fold greater in the denervated than in the innervated eye, but was unaltered in lacrimal gland, cerebral cortex, and masseter muscle. Choroid surface area was not affected by long-term sympathectomy, but choroidal thickness was increased and choroidal cross-sectional area occupied by vascular lumina was greater. Arteriolar number per unit cross-sectional area of choroid was not altered although arteriolar diameters were enlarged. Choroidal venules were larger and more abundant. Choroidal capillary numbers were unchanged, but retinal capillaries of the outer plexiform layer were increased. To determine if these changes result from loss of sympathetic activity, sympathetic preganglionic innervation was excised chronically. This produced significant increases in choroidal thickness and vascular luminal area, and in numbers of arterioles, small venules, and capillaries in the outer plexiform layer. These findings show that sympathetic innervation is critical in regulating choroidal and retinal vascularity, and that chronic loss of sympathetic activity may contribute to abnormal vascular proliferation in diseases such as age-related macular degeneration and diabetic retinopathy. (C) 2002 Elsevier Science Ltd.