AJP - Renal Physiology, Vol 244, Issue 3 349-F354, Copyright © 1983 by American Physiological Society
In vitro perfusion of the isolated dog glomerulus
R. W. Osgood, M. Patton, M. J. Hanley, M. Venkatachalam, H. J. Reineck and J. H. Stein
Recent technological advances allowing direct in vivo measurements of the
determinants of glomerular ultrafiltration have greatly expanded our
understanding of that process. In addition, these in vivo studies have
clarified the dynamics of glomerular ultrafiltration in a number of
physiologic and pathophysiologic conditions. Despite this progress,
important issues remain unresolved and beyond the scrutiny of in vivo
techniques. We have therefore devised a technique for in vitro glomerular
perfusion of the isolated dog glomerulus. In eight glomeruli perfused at
physiologic rates, the glomerular filtration rate averaged 39 nl/min and
the filtration fraction was 0.19. Filtration pressure disequilibrium was
observed in all studies and thus allowed calculation of a unique value for
the ultrafiltration coefficient. That parameter averaged 2.34 nl/(min X
mmHg). Morphologic studies employing transmission electron microscopy
indicate that isolated perfused glomeruli remain ultrastructurally intact.
The method for glomerular isolation and in vitro perfusion is presented in
detail, the results obtained are compared with published in vivo results,
and the advantages offered by the technique are discussed.
