Wandolo G, Elias R M, Ranadive N S, Johnston M G
Trauma Research Program, Sunnybrook Health Science Centre, Toronto, Canada.
J Vasc Res. 1992 May-Jun;29(3):248-55. doi: 10.1159/000158939.
Red blood cells (RBCs) and lysate products (erythrolysate) are consistently observed in lymph draining inflammatory reactions and from tissues subjected to trauma or surgical procedures. We determined previously that erythrolysate modulates lymphatic pumping by altering the pressures over which the lymph pump is active. The purpose of this study was to test the hypothesis that oxyhemoglobin was the active material within erythrolysate. To quantitate lymphatic pumping, bovine lymphatics were suspended in an organ bath preparation with the vessels cannulated at both inflow and outflow ends. By raising the heights of the Krebs reservoir and the outflow catheters appropriately, a transmural pressure could be applied to the vessels. This procedure stimulated pumping activity. Erythrolysate was prepared from sheep RBCs by lysis in Tris buffer and a portion of this was purified by column chromatography using DEAE-Sephadex A-50. Both the purified hemoglobin (10(-5) M) and crude erythrolysate (the latter diluted appropriately in Krebs solution to contain 10(-5) M hemoglobin) reduced lymphatic fluid pumping approximately 70% over a period of 2 h. To determine whether this activity was due to the heme or the protein portion of the molecule, we compared the activity of purified oxyhemoglobin with that of its oxidized methemoglobin derivative. This was achieved by conversion with potassium ferricyanide. Methemoglobin was inactive, suggesting that the heme portion was important for the lymphatic effect. Further confirmation of this observation was provided by experiments with myoglobin which was purified from sheep heart. Oxymyoglobin, which shares an identical heme but has a different protein component, inhibited lymphatic pumping, when tested on the bovine lymphatics.(ABSTRACT TRUNCATED AT 250 WORDS)
在引流炎症反应的淋巴液以及遭受创伤或外科手术的组织中，始终能观察到红细胞（RBCs）和裂解产物（红细胞裂解液）。我们之前已确定，红细胞裂解液通过改变淋巴泵活动时的压力来调节淋巴泵血。本研究的目的是验证氧合血红蛋白是红细胞裂解液中的活性物质这一假说。为了定量淋巴泵血，将牛淋巴管置于器官浴制备装置中，血管的流入端和流出端均插管。通过适当升高Krebs贮液器和流出导管的高度，可向血管施加跨壁压力。此操作可刺激泵血活动。红细胞裂解液由绵羊红细胞在Tris缓冲液中裂解制备，其中一部分通过使用DEAE - Sephadex A - 50的柱色谱法进行纯化。纯化的血红蛋白（10⁻⁵ M）和粗制红细胞裂解液（后者在Krebs溶液中适当稀释以含有10⁻⁵ M血红蛋白）在2小时内均使淋巴液泵血减少约70%。为了确定这种活性是由于分子的血红素部分还是蛋白质部分，我们比较了纯化的氧合血红蛋白与其氧化型高铁血红蛋白衍生物的活性。这通过用铁氰化钾转化来实现。高铁血红蛋白无活性，表明血红素部分对淋巴效应很重要。从绵羊心脏纯化的肌红蛋白实验进一步证实了这一观察结果。当在牛淋巴管上进行测试时，与血红素相同但蛋白质成分不同的氧合肌红蛋白抑制了淋巴泵血。（摘要截断于250字）
