Perivascular adipose tissue modulates vascular function in the human internal thoracic artery
Perivascular adipose tissue modulates vascular function in the human internal thoracic artery
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DOI：
10.1016/j.jtcvs.2005.05.028
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发表时间：
2005-10-01
影响因子：
6
通讯作者：
Lee, RMKW
中科院分区：
文献类型：
--
作者：
Gao, YJ;Zeng, ZH;Lee, RMKW
目的：最近的研究表明，大鼠主动脉血管周围脂肪组织分泌一种能扩张主动脉的物质。本研究的目的是研究这种血管扩张剂是否也存在于人类胸内动脉中。方法：采用钢丝肌造影和光镜观察人胸椎内动脉有无血管周围脂肪组织的血管功能。结果：血管周围脂肪组织的存在使u46619的最大收缩力和苯肾上腺素（1 μ mol/L）的最大收缩力分别减弱37%和24%。将与血管周围脂肪组织完整的血管（供体）孵育的溶液转移到没有血管周围脂肪组织的血管（受体）中，在用苯肾上腺素预收缩的受体动脉中诱导了显著的松弛（36%）。仅用血管周围脂肪组织转移培养液也能诱导受体血管的松弛反应（37%）。在KCl （60 mmol/L）预收缩的血管中，由供体（血管周围脂肪组织完整的动脉或血管周围脂肪组织单独存在的动脉）转移的培养液诱导的受体动脉松弛在KCl （60 mmol/L）预收缩的血管中不存在，并被钙依赖性钾通道阻滞剂(四乙基氯化铵，1 mmol/L；而电压依赖性钾通道阻滞剂4-氨基吡啶（1 mmol/L）和三磷酸腺苷依赖性钾通道阻滞剂格列本脲（10 μ mol/L）则没有作用。结论：人胸内动脉血管周围脂肪组织释放一种可转移的松弛因子，通过激活钙依赖性钾通道起作用。由于在冠状动脉旁路移植术中经常去除血管周围脂肪组织，保留血管周围脂肪组织可能有助于减少移植血管痉挛的发生。
Objective: Recent studies have shown that perivascular adipose tissue from the rat aorta secretes a substance that can dilate the aorta. The purpose of the present study was to examine whether this vasodilator is also present in human internal thoracic arteries.Methods: Vascular function of human internal thoracic arteries with and without perivascular adipose tissue was assessed with wire myography, and morphology was examined with light microscopy.Results: The presence of perivascular adipose tissue attenuated the maximal contraction to U 46619 and the contraction to phenylephrine (1 mu mol/L) by 37% and 24%, respectively. Transfer of the solution incubated with a perivascular adipose tissue-intact vessel (donor) to a vessel without perivascular adipose tissue (recipient) induced a significant relaxation (36%) in the recipient artery precontracted with phenylephrine. Transfer of incubation solution with perivascular adipose tissue alone also induced a relaxation response in the recipient vessel (37%). The relaxation of the recipient artery induced by the transfer of incubation solution from the donor (artery with intact perivascular adipose tissue or perivascular adipose tissue alone) was absent in vessels precontracted by KCl (60 mmol/L) and was prevented by calcium-dependent potassium channel blockers (tetraethylammonium chloride, 1 mmol/L; iberiotoxin, 100 nmol/L), but not by the voltage-dependent potassium channel blocker 4-aminopyridine (1 mmol/L) and the adenosine triphosphate-dependent potassium channel blocker glibenclamide (10 mu mol/L).Conclusions: Perivascular adipose tissue in human internal thoracic arteries releases a transferable relaxation factor that acts through the activation of calcium-dependent potassium channels. Because perivascular adipose tissue is often removed in coronary artery bypass grafting, retaining perivascular adipose tissue might be helpful in reducing the occurrence of vasospasm of the graft vessels.