UPTAKE OF OCHRATOXIN-A BY SLICES OF PIG-KIDNEY CORTEX
UPTAKE OF OCHRATOXIN-A BY SLICES OF PIG-KIDNEY CORTEX
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DOI：
10.1016/0300-483x(88)90205-3
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发表时间：
1988-11-14
期刊：
影响因子：
4.5
通讯作者：
HALD, B
中科院分区：
文献类型：
--
作者：
FRIIS, C;BRINN, R;HALD, B
赭曲霉毒素A(OCT A)是一种导致近曲小管选择性坏死的肾毒素。OCTA是一种有机阴离子，有望通过有机阴离子转运系统进入肾小管细胞。猪肾皮质切片用于表征OCTA的转运。10月5日(5：00)10-3 mm)在浓度梯度下累积，切片与介质的比率为8.9.+-。2.9在氧气存在的情况下。在氮气气氛中(S/M=2.9.+-)，这种积累明显减少。0.5)。OCT A的积累依赖于培养基浓度。随着浓度的增加(5.倍。10-5-5次。10-1 mm)，切片与中层的比例最初从6.9+-上升。2.0至11.7。+-。1.2于是降至5.4.+-。1.1.这一模式表明，载体介导的转运和细胞内代谢可能都有助于毒素的净积累。OCT A(10-4~1 mM)以剂量依赖方式抑制对氨基马尿酸(PAH)和酚磺胺(PSP)的摄取。在10-1 mM时，OCT A不抑制多环芳烃的乙酰化，表明有氧代谢和运输过程的能量供应没有受到影响。动力学研究表明，PSP转运受到竞争性抑制。结论：OCTA通过共同的有机阴离子转运系统进入近端小管细胞。
Ochratoxin A (OCT A) is a nephrotoxin causing selective necrosis of the proximal tubule. Being an organic anion OCT A might be expected to enter the tubule cells by the organic anion transport system. Pig renal cortical slices were used to characterize the OCT A transport. OCT (5 .times. 10-3 mM) was accumulated against a concentration gradient with a slice to medium ratio of 8.9 .+-. 2.9 in the presence of oxygen. This accumulation was markedly reduced in a nitrogen atmosphere (S/M ratio = 2.9 .+-. 0.5). OCT A accumulation was dependent on medium concentration. With increasing concentration (5 .times. 10-5-5 .times. 10-1 mM), slice to medium ratio initially rose from 6.9 .+-. 2.0 to 11.7 .+-. 1.2 whereupon it declined to 5.4 .+-. 1.1. This pattern indicates that both carrier mediated transport and intracellular metabolism may contribute to the net accumulation of the toxin. OCT A (10-4 to 1 mM) inhibited p-aminohippurate (PAH) and phenolsulphophalein (PSP) uptake in a dose-dependent manner. Up to 10-1 mM, OCT A did not inhibit acetylation of PAH suggesting that aerobic metabolism and the energy supply for the transport process were unaffected. Kinetic studies revealed a competitive inhibition of the PSP transport. It is concluded that OCT A enters the proximal tubule cells by the common organic anion transport system.