Cojocel C, Franzen-Sieveking M, Beckmann G, Baumann K
Pflugers Arch. 1981 Jun;390(3):211-5. doi: 10.1007/BF00658263.
Together the two rat kidneys accumulated a total of 31.7 +/- 1.6% of the intravenously injected amount of 7 nmoles egg-white-lysozyme (measured as iodine 125 lysozyme) within 10 min. The low molecular weight protein lysozyme and other basic substances were injected simultaneously in order to evaluate whether these basic substances can inhibit the renal lysozyme accumulation. The inhibitory effect of various basic compounds was dose-dependent with a maximal reduction of lysozyme accumulation to 11.7 +/- 0.08%. The basic substances could be divided into three groups depending upon the micromolar amount injected at which a 50% inhibition was achieved (0.3-1.2 micromoles: cytochrome C, ribonuclease; 10.9 micromoles; spermine; 501-688 micromoles: L-arginine, L-lysine). The neutral myoglobin had no effect on renal lysozyme accumulation. The inhibitory potency appeared to increase with increasing molecular weight and pI value of the substance tested. Microperfusion experiments of proximal convoluted tubules of rat kidney revealed that luminal reabsorption of the basic lysozyme can be inhibited by the basic protein cytochrome C in a dose-dependent fashion. In these experiments the perfusion solution contained 57 micromol .l-1 lysozyme, an intratubular lysozyme concentration at which the tubular lysozyme reabsorption was found to be about 80% saturated. A 50% inhibition of the tubular endocytic lysozyme reabsorption was achieved a cytochrome C concentration of 102 micromol.l-1.
在10分钟内，两只大鼠肾脏总共积累了静脉注射的7纳摩尔蛋清溶菌酶（以碘125溶菌酶测量）总量的31.7±1.6%。同时注射低分子量蛋白质溶菌酶和其他碱性物质，以评估这些碱性物质是否能抑制肾脏溶菌酶的积累。各种碱性化合物的抑制作用呈剂量依赖性，溶菌酶积累的最大减少量为11.7±0.08%。根据达到50%抑制率时注射的微摩尔量，碱性物质可分为三组（0.3 - 1.2微摩尔：细胞色素C、核糖核酸酶；10.9微摩尔：精胺；501 - 688微摩尔：L-精氨酸、L-赖氨酸）。中性的肌红蛋白对肾脏溶菌酶的积累没有影响。抑制效力似乎随着被测物质分子量和pI值的增加而增强。大鼠肾脏近端曲管的微灌注实验表明，碱性蛋白质细胞色素C能以剂量依赖性方式抑制碱性溶菌酶的管腔重吸收。在这些实验中，灌注液含有57微摩尔·升⁻¹溶菌酶，这是一个发现肾小管溶菌酶重吸收约80%饱和的管内溶菌酶浓度。细胞色素C浓度为102微摩尔·升⁻¹时，实现了肾小管内吞性溶菌酶重吸收50%的抑制。
