The influence of sampling technique on the micropuncture determination of GFR and reabsorptive characteristics of single rat proximal tubules
- 29 Downloads
Studies have been carried out in order to assess the validity of the determination of the single nephron filtration rate by micropuncture techniques. By means of a double microscope and two investigators operating simultaneoulsy, intratubular pressure and single nephron transit time were recorded during sampling. The data indicate that collection of tubular fluid by means of aspiration significantly accelerates transit time, decreases intratubular pressure, and results in an increase of single nephron filtration rate. In contrast, spontaneously flowing collections were associated with insignificant alterations of transit time and intratubular pressure. Technical details underlying these observations have to some extent been delineated. The importance of these data with respect to artifactual alterations of single nephron parameters is discussed.
Key-WordsMicropuncture Sampling Technique Single Nephron GFR Intratubular Pressure Reabsorptive Capacity
SchlüsselwörterMikropunktion Sammeltechnik Einzelnephronfiltrat intratubulärer Druck Resorptionskapazität
Unable to display preview. Download preview PDF.
- 1.Biber, T. U. L., M. Mylle, A. D. Baines, C. W. Gottschalk, J. R. Oliver, andM. C. MacDowell: A study by micropuncture and microdissection of acute renal damage in rats. Amer. J. Med.44, 664 (1968).Google Scholar
- 2.Brenner, B. M., C. M. Bennett, andR. W. Berliner: The relationship between glomerular filtration rate and sodium reabsorption by the proximal tubule of the rat nephron. J. clin. Invest.47 1358 (1968).Google Scholar
- 3.Gertz, K. H.: Transtubuläre Natriumchloridflüsse und Permeabilität für Nichtelektrolyte im proximalen und distalen Konvolut der Rattenniere. Pflügers Arch. ges. Physiol.276, 336 (1963).Google Scholar
- 4.Gottschalk, C. W., andP. P. Leyssac: Proximal tubular function in rats with low inulin clearance. Acta physiol. scand.74, 453 (1968)Google Scholar
- 5.Hayslett, J. P., M. Kashgarian, andF. H. Epstein: Functional correlates of compensatory renal hypertrophy. J. clin. Invest.47, 774 (1968).Google Scholar
- 6.Horster, M., andK. Thurau: Micropuncture studies on the filtration rate of single superficial and juxtamedullary glomeruli in the rat kidney. Pflügers Arch. ges. Physiol.301, 162 (1968).Google Scholar
- 7.Landwehr, D. M., J. Schnermann, R. M. Klose andG. Giebisch: The effect of acute reduction in glomerular filtration rate in renal tubular sodium and water reabsorption. Amer. J. Physiol.215, 687 (1968).Google Scholar
- 8.Levine, D. Z., G. Liebau, H. Fischbach, andK. Thurau: Micropuncture studies on the dog kidney. II. Reabsorptive characteristics of the proximal tubule during spontaneous and experimental variations in GFR and during drug induced natriuresis. Pflügers Arch.304, 365 (1968).Google Scholar
- 9.Schnermann, J., D. Z. Levine, andM. Horster: A direct evaluation of the Gertz hypothesis on single rat proximal tubules in vivo: Failure of the tubular volume to be the sole determinant of the reabsorptive rate. Pflügers Arch.308, 149 (1969).Google Scholar