Dietary protein restriction in rats with bilateral ureteral obstruction

限制蛋白质饮食可改善双侧输尿管梗阻（BUO）后24小时出现的GFR和肾血浆流量下降。血管活性激素，前列腺素（PG）和血栓素（Tx），在上述肾功能的变化中起作用。因此，我们评估了饮食蛋白限制对<1alpha>从假手术对照（SOC）和BUO大鼠中分离的肾小球中PGE_2、6-ketoPGF_2和TxB_2的产生以及对环氧合酶和磷脂酶A_2和C的活性的影响，所述BUO大鼠喂食低蛋白（6%酪蛋白）或正常蛋白（23%酪蛋白）饮食约4周。与低蛋白饮食相比，正常蛋白饮食可显著增加SOC大鼠肾小球PGE_2、6-ketoPGF_2和TxB_2的生成<1alpha>。与正常蛋白质饮食的SOC大鼠相比，BUO大鼠肾小球中类花生酸的产生进一步增加。类花生酸的生成速率与 ...更多信息 两组大鼠环氧合酶活性均无显著性差异。另一方面，低蛋白饮食完全取消了肾小球类花生酸生产的增加与BUO大鼠。类花生酸的合成水平在低蛋白饲料SOC和BUO大鼠相当，表明正常化的肾小球类花生酸生产在BUO大鼠喂养低蛋白饮食。此外，环氧合酶和磷脂酶A_2和C的活性在SOC和BUO大鼠之间无显著差异。我们以前的研究表明，环氧合酶和磷脂酶A_2活性的增加在BUO大鼠肾小球类花生酸的产生中起关键作用，因此，我们的研究结果表明，在BUO持续24小时的情况下，限制饮食蛋白质可阻止由于磷脂酶A_2和环氧合酶失活而引起的肾小球类花生酸产生的增加。限制蛋白质饮食对BUO大鼠肾功能的保护作用可能部分是由于肾小球生成类花生酸，特别是TxA_2的正常化。少

Dietary protein restriction ameliorates the decrease in GFR and renal plasma flow that occurs 24 hours after the onset of bilateral ureteral obstruction (BUO). The vasoactive hormones, prostaglandins (PGs) and thromboxane (Tx), have a role in the changes in renal function described above. Thus, we evaluated the effect of dietary protein restriction on the production of PGE_2.6-keto PGF_<1alpha> and TxB_2 and on the activities of cyclooxygenase and phospholipases A_2 and C in glomeruli isolated from sham-operated control (SOC) and BUO rats fed a low (6% casein) or a normal protein (23% casein) diet for approximately 4 weeks. A normal protein diet compared to a low protein diet significantly increased the glomerular production of PGE_2,6-keto PGF_<1alpha> and TxB_2 in SOC rats. Glomeruli of rats with BUO fed a normal protein diet had further increased production of eicosanoids when compared to glomeruli of SOC rats ingesting the same diet. The production rates of eicosanoids correlated w … More ell with the activity of cyclooxygenase in the two groups of rats. On the other hand, a low protein diet completely abolished the increase in glomerular eicosanoid production seen in rats with BUO.The synthetic levels of eicosanoids were comparable in low protein-fed SOC and BUO rats, indicating normalization of glomerular eicosanoid production in BUO rats fed a low protein diet. Moreover, there were no significant differences in the activities of cyclooxygenase and phospholipases A_2 and C between the SOC and BUO rats. We demonstrated previously that increases in the activities of cyclooxygenase and phospholipase A_2 have a key role in glomerular eicosanoid production in rats with BUO.Thus, our results indicate that dietary protein restriction prevents the increase in production of eicosanoids by glomeruli due to inactivation of phospholipase A_2 and cyclooxygenase in the setting of BUO of 24 hours duration. The protective effect of dietary protein restriction on renal function in rats with BUO may be due in part to normalization of the glomerular production of eicosanoids, particularly TxA_2. Less