Kohan D E, Schreiner G F
Department of Medicine, Washington University School of Medicine, St. Louis, Missouri 63110.
Am J Physiol. 1988 Jun;254(6 Pt 2):F879-86. doi: 10.1152/ajprenal.1988.254.6.F879.
We have investigated the effect of immune factors on glucose and amino acid transport by proximal tubular epithelium. Proximal tubular cells were obtained by enzymatic digestion of mouse renal cortex and grown to confluent monolayers. alpha-[14C]methylglucoside (AMG), D-[3H]-aspartate, L-[3H]leucine, and L-[3H]arginine uptake were assayed. Proximal tubular epithelium coincubated with supernatants derived from lipopolysaccharide (LPS)-stimulated mouse peritoneal macrophages had a twofold increase in AMG and aspartate uptake that was sodium dependent, was prevented by cycloheximide or actinomycin D, and was not associated with changes in cell growth or differentiation. Chromatographic separation of the macrophage supernatant yielded one fraction, mol wt 16,000-20,000, that enhanced AMG and aspartate uptake and contained interleukin 1 (IL 1) determined by bioassay. Recombinant IL 1 (mol wt 17,500) reproduced changes in AMG and aspartate uptake seen with macrophage supernatants. In contrast, neither macrophage supernatants nor IL 1 affected sodium-independent leucine or arginine transport. IL 1 directly increased 22Na transport into proximal tubular cells. These data indicate that macrophages, via IL 1 secretion, are capable of modulation of sodium-linked solute transport in proximal tubular epithelium.
我们研究了免疫因子对近端肾小管上皮细胞葡萄糖和氨基酸转运的影响。通过酶消化小鼠肾皮质获得近端肾小管细胞，并使其生长至汇合单层。测定了α-[¹⁴C]甲基葡萄糖苷（AMG）、D-[³H]天冬氨酸、L-[³H]亮氨酸和L-[³H]精氨酸的摄取。与脂多糖（LPS）刺激的小鼠腹腔巨噬细胞来源的上清液共同孵育的近端肾小管上皮细胞，AMG和天冬氨酸摄取增加了两倍，这种增加依赖于钠，可被放线菌酮或放线菌素D阻止，且与细胞生长或分化的变化无关。对巨噬细胞上清液进行色谱分离得到一个分子量为16,000 - 20,000的组分，该组分增强了AMG和天冬氨酸的摄取，通过生物测定法确定其含有白细胞介素1（IL 1）。重组IL 1（分子量17,500）重现了巨噬细胞上清液所见的AMG和天冬氨酸摄取变化。相比之下，巨噬细胞上清液和IL 1均不影响不依赖钠的亮氨酸或精氨酸转运。IL 1直接增加了²²Na向近端肾小管细胞的转运。这些数据表明，巨噬细胞通过分泌IL 1，能够调节近端肾小管上皮细胞中与钠相关的溶质转运。
