Isolated tubules

Isolated perfused kidney Isolated tubules Renal cells Cell lines Primary cells Kidney slices Isolated organelles... 

In the isolated perfused kidney model, the artery of the kidney is perfused and urinary samples as well as venous blood samples can be collected to determine the drug concentration. A serious drawback of the model is that isolation and artificial perfusion greatly affect the function of the organ as shown by a dramatic drop in the glomerular filtration rate. Another in-vitro model is the isolated tubule in which samples can be taken from both the luminal and basolateral sites of the tubule [140,141]. The disadvantage of this technique as well as of the isolated kidney model, is that they require specific equipment and expertise and therefore can only be performed in rather specialized laboratories. Experiments using freshly isolated or cultured cells are more simple to carry out [142,143]. Tubular cells can be grown in a po-... 

Vandewalle A, Farman N, Morin JP, Fillastre JP, Hatt PY, Bonvalet JP, Gastineau M, Wanstok F, Gentamicin incorporation along the nephron autoradiographic study on isolated tubules. Kidney Int, 1981 19 529-39. 

Horster MF, Sone M. Primary culture of isolated tubule cells of defined segmental origin. Methods Enzymol 1990 191 409-426. 

Jackson, B.A., Edwards, R.M. and Dousa, T.P. (1980). Vasopressin-prostaglandin interactions in isolated tubules from rat outer medulla. ]. Lab. Clin. Med., 96, 119-28... 

Lang et al., 1978) or microperfusion of isolated tubules (in vitro) (Chonko et al 1975) are needed. Wheras the micropuncture method cannot be used in man for ethical reasons, in vitro microperfusion may be used however the dissection of tubules from pieces of human kidneys is difficult and kidneys are rarely available. 

Unfortunately, at the present time there appears to be no alternative method for evaluating the renal transport of uric acid in man which is superior to the PZA suppression test. It would therefore appear reasonable to determine if a process is or is not blocked by PZA pretreatment. However, we would recommend that interpretation of the response be limited and that one not attempt to associate any response with a specific abnormality of transport. Perhaps, an effect blocked by PZA should be considered a Type A response and an effect not blocked by this agent a Type B response. Hopefully, in the future we will have the additional data necessary to determine the molecular or at least physiological basis for a Type A and Type B response. Indeed, with the recent demonstrations that the New World Monkey, a species that does not have uricase activity, handles uric acid in a similar if not identical manner to man, it may be possible to design micropuncture, isolated tubule and other in vitro experiments that will provide direct data on the sites and mechanisms concerned with uric acid transport in the kidney. 

Agarwal, A. Measuring A P m in isolated tubules. Am. J. Physiol. 2005, 288, F1090-F1091. 

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