Retinal arterial tone is controlled by a retinal-derived relaxing factor.
Retinal arterial tone is controlled by a retinal-derived relaxing factor.
复制标题
视网膜动脉张力由视网膜衍生的松弛因子控制。
DOI：
10.1161/01.res.83.7.714
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发表时间：
1998
影响因子：
20.1
通讯作者：
J. van de Voorde
中科院分区：
文献类型：
--
作者：
C. Delaey;J. van de Voorde
本研究提供的证据表明，视网膜组织可能通过释放未知的视网膜松弛因子来深刻影响视网膜动脉平滑肌细胞的张力。将有或没有粘附视网膜组织的离体牛视网膜动脉安装在钢丝肌动描记器中以进行等长张力记录。在存在粘附视网膜组织的情况下，前列腺素F2α诱导的最大收缩为0.95+/-0.7 mN (n=6)，在不存在粘附视网膜组织的情况下，前列腺素F2α诱导的最大收缩为5.15+/-0.76 mN (n=6)。在视网膜组织存在的情况下，U-46619、血清素和内皮素-1 诱导的收缩同样被阻断。 K+ 120 mmol/L 诱导的收缩未受到显着影响（存在视网膜组织时为 2.8+/-0.7 mN，n=6，不存在视网膜组织时为 3. 6+/-0.7 mN，n=6）。将一块牛视网膜组织放置在收缩的（即含有前列腺素F2α的）视网膜动脉附近会诱导视网膜血管完全松弛，这表明存在可扩散的化学血管舒张剂。猪、犬和羊的视网膜组织也完全放松了收缩的（前列腺素 F2α）牛视网膜动脉。其他平滑肌制剂，包括大鼠肠系膜和肾动脉以及大鼠主支气管，也通过应用一块牛视网膜组织而松弛。将牛视网膜在克雷布斯-林格碳酸氢盐溶液中孵育，得到的溶液可以松弛分离的预先收缩的牛视网膜动脉，证实了可扩散化学信使的参与。己烷提取、将溶液加热至 70 摄氏度或用胰蛋白酶处理不会改变孵育溶液的松弛特性。视网膜松弛因子的特性与一氧化氮、前列腺素类、腺苷、乙酰胆碱或任何其他已知的从视网膜释放的血管活性神经递质的特性不对应。我们的结果表明，视网膜动脉张力是由可扩散、亲水和热稳定的松弛因子控制的，该因子与视网膜内形成的已知血管活性分子不对应。
The present study provides evidence that retinal tissue may profoundly influence the retinal arterial smooth muscle cell tone by releasing an unknown retinal relaxing factor. Isolated bovine retinal arteries with and without adhering retinal tissue were mounted in a wire myograph for isometric tension recordings. The maximal contraction induced by prostaglandin F2alpha was 0.95+/-0.7 mN (n=6) in the presence and 5.15+/-0.76 mN (n=6) in the absence of adhering retinal tissue. The contractions induced by U-46619, serotonin, and endothelin-1 were similarly blocked in the presence of retinal tissue. The K+ 120 mmol/L-induced contraction was not significantly affected (2.8+/-0.7 mN, n=6, in the presence and 3. 6+/-0.7 mN, n=6, in the absence of retinal tissue). Placing a piece of bovine retinal tissue in the proximity of a contracted (ie, with prostaglandin F2alpha) retinal artery induced a complete relaxation of the retinal vessel, suggesting the involvement of a diffusible chemical vasorelaxant. Also porcine, canine, and ovine retinal tissue completely relaxed the contracted (with prostaglandin F2alpha) bovine retinal artery. Other smooth muscle preparations, including rat mesenteric and renal arteries and rat main bronchi, also relaxed with the application of a piece of bovine retinal tissue. Incubation of bovine retinas in a Krebs-Ringer bicarbonate solution yielded a solution that relaxed isolated precontracted bovine retinal arteries, confirming the involvement of a diffusible chemical messenger. Hexane extraction, heating the solution to 70 degrees C, or treatment with trypsin did not alter the relaxing properties of the incubation solution. The characteristics of the retinal relaxing factor do not correspond with those of nitric oxide, prostanoids, adenosine, acetylcholine, or any other of the known vasoactive neurotransmitters released from the retina. Our results suggest that retinal arterial tone is controlled by a diffusible, hydrophilic, and heat-stable relaxing factor that does not correspond with a known vasoactive molecule formed within the retina.