Kiener J L, Saba T M, Cho E, Blumenstock F A
Am J Physiol. 1986 Oct;251(4 Pt 2):R724-34. doi: 10.1152/ajpregu.1986.251.4.R724.
Fibronectin is a glycoprotein found in a soluble form in plasma and in an insoluble form in many tissues. We evaluated the influence of postoperative intraperitoneal sepsis on the clearance, tissue distribution, and synthesis of plasma fibronectin in rats (300-400 g). Experimental sepsis was induced by cecal ligation following laparotomy, whereas control animals underwent laparotomy (5 cm) alone. At 24 and 48 h after laparotomy, plasma fibronectin levels were normal. After laparotomy plus cecal ligation, plasma fibronectin increased by 47% at 24 h and remained elevated (52% above 0 time) at 48 h. At 24 h postsurgery the disappearance and tissue distribution of 75Se-plasma fibronectin and 75Se-plasma albumin was evaluated. Tissue distribution was quantified at 2 and 24 h after intravenous injection of both tracer proteins in separate groups. Both fibronectin and albumin demonstrated an initial distribution between vascular and extravascular sites and then a progressive decrease in plasma. In control (laparotomy) rats the half-life (t1/2) for plasma clearance of 75Se-plasma fibronectin was 25.33 +/- 2.53 h compared with 13.21 +/- 0.78 h in the septic rats. Septic rats manifested decreased sequestration of 75Se-fibronectin at the area of surgical incision (laparotomy), increased sequestration at the focus of intraperitoneal infection, and increased uptake in the nonviable portion of the cecum. The synthetic rate for plasma fibronectin in laparotomized control rats was 3.03 +/- 0.29 mg X 100 g-1 X 24 h-1, whereas after laparotomy plus cecal ligation the synthetic rate increased to 4.58 +/- 0.35 mg X 100 g-1 X 24 h-1. In contrast the synthetic rate for albumin decreased from 84.70 +/- 1.66 mg X 100 g-1 X 24 h-1 in controls to 52.38 +/- 1.77 mg X 100 g-1 X 24 h-1 in the septic animals. Thus intraperitoneal sepsis in the rat will enhance the vascular clearance, alter the distribution, and increase the synthetic rate for plasma fibronectin.
纤连蛋白是一种糖蛋白，在血浆中以可溶形式存在，在许多组织中以不溶形式存在。我们评估了术后腹腔感染对大鼠（300 - 400克）血浆纤连蛋白清除率、组织分布及合成的影响。通过剖腹术后结扎盲肠诱导实验性感染，而对照动物仅接受剖腹术（5厘米）。剖腹术后24小时和48小时，血浆纤连蛋白水平正常。剖腹术加盲肠结扎后，血浆纤连蛋白在24小时时增加了47%，并在48小时时仍保持升高（比0小时时高52%）。在术后24小时评估了75Se - 血浆纤连蛋白和75Se - 血浆白蛋白的消失及组织分布情况。在单独的组中静脉注射两种示踪蛋白后，于2小时和24小时对组织分布进行定量分析。纤连蛋白和白蛋白均首先在血管和血管外部位分布，然后血浆中含量逐渐降低。在对照（剖腹术）大鼠中，75Se - 血浆纤连蛋白的血浆清除半衰期（t1/2）为25.33±2.53小时，而在感染大鼠中为13.21±0.78小时。感染大鼠在手术切口（剖腹术）部位的75Se - 纤连蛋白潴留减少，在腹腔感染灶的潴留增加，并且在盲肠坏死部分的摄取增加。剖腹术对照大鼠中血浆纤连蛋白的合成速率为3.03±0.29毫克×100克-1×24小时-1，而剖腹术加盲肠结扎后合成速率增至4.58±0.35毫克×100克-1×24小时-1。相比之下，白蛋白的合成速率从对照中的84.70±1.66毫克×100克-1×24小时-1降至感染动物中的52.38±1.77毫克×100克-1×24小时-1。因此，大鼠腹腔感染会增强血管清除率、改变分布并增加血浆纤连蛋白的合成速率。
