Walker R J, Lazzaro V A, Duggin G G, Horvath J S, Tiller D J
Department of Renal Medicine, Royal Prince Alfred Hospital, Camperdown, New South Wales, Australia.
Transplantation. 1989 Aug;48(2):321-7. doi: 10.1097/00007890-198908000-00026.
Proximal (LLC-PK1) and distal (MDCK) renal epithelial cell cultures were used to investigate early biochemical changes in cellular metabolism following exposure to cyclosporine A (CsA). 3H-thymidine and 3H-leucine incorporation into the cells were used as indices of DNA and protein synthesis. The cells were exposed to concentrations of CsA ranging from 0.2 microgram/ml to 20 micrograms/ml. By 20 hr there was a decrease in the total cell count at concentrations of 10 and 20 micrograms/ml that was more pronounced by 5 days of exposure. At 5 days there was also a reduction in cell count at the lower concentrations of CsA. There was an initial increase in DNA and protein synthesis at 2 hr with inhibition of DNA synthesis evident by 20 hr. Protein synthesis was increased in the LLC-PK1 cells and decreased in the MDCK cells. At 5 days there was evidence of increased DNA and protein synthesis, most marked in the remaining viable cells exposed to the higher concentrations of CsA. Similar alterations in cellular metabolism were evident when the cells were exposed to the immunologically inert cyclosporine H (D-N-MeVal11-Cs). These studies demonstrate that cyclosporine produces alterations in cellular function as early as 2 hr after exposure to the drug. At the lower concentrations there is evidence of sublethal cellular toxicity and cellular regeneration. The toxicity appears to be related to the molecular structure of cyclosporine and its incorporation into cell membranes. We postulate that cyclosporine nephrotoxicity is the summation of several subtoxic alterations in cellular function the final expression of which is modified by other factors affecting renal function.
采用近端（LLC-PK1）和远端（MDCK）肾上皮细胞培养物来研究环孢素A（CsA）作用后细胞代谢早期的生化变化。将3H-胸苷和3H-亮氨酸掺入细胞作为DNA和蛋白质合成的指标。细胞暴露于浓度范围为0.2微克/毫升至20微克/毫升的CsA中。到20小时时，浓度为10微克/毫升和20微克/毫升时总细胞数减少，暴露5天时这种减少更明显。在5天时，较低浓度的CsA也会使细胞数减少。DNA和蛋白质合成在2小时时最初增加，到20小时时DNA合成受到明显抑制。LLC-PK1细胞中的蛋白质合成增加，而MDCK细胞中的蛋白质合成减少。在5天时，有证据表明DNA和蛋白质合成增加，在暴露于较高浓度CsA的存活细胞中最为明显。当细胞暴露于免疫惰性的环孢素H（D-N-MeVal11-Cs）时，细胞代谢也有类似变化。这些研究表明，环孢素在接触药物后2小时就会引起细胞功能改变。在较低浓度时，有亚致死性细胞毒性和细胞再生的证据。毒性似乎与环孢素的分子结构及其掺入细胞膜有关。我们推测，环孢素肾毒性是细胞功能中几种亚毒性改变的总和，其最终表现会受到影响肾功能的其他因素的修饰。
