Renal Blood Flow
The microcirculation of the kidney is unique. Most organs are relatively homogeneously prefused by arteries and veins that are interconnected by a capillary bed that supplies oxygen and nutrients to the tissue. In contrast, the perfusion of the kidney is highly heterogeneous. Tissue blood flows range from 700 ml • min-1 • 100g-1 of tissue in the renal cortex to around 50 ml • min-1 • 100g-1 of tissue in the renal papilla [1–5]. Moreover, there are structural differences in the microvasculature in various regions of the kidney, and each region contains specialized vascular structures that serve the excretory function of the kidney [6, 7]. In this regard, the renal vasculature not only supplies the metabolic needs of the tissue, but it also ultrafilters solutes and water into the tubular system, reabsorbs tubular fluid, preserves the osmotic gradient in the renal medulla, and regulates tubular function by influencing the composition of, and the hydrostatic pressure in, the renal interstitium.
KeywordsRenal Blood Flow Renal Cortex Outer Medulla Tissue Blood Flow Electromagnetic Flowmeter
Unable to display preview. Download preview PDF.
- 1.Brenner, B.M., R. Zatz, and I. Ichikawa. 1986. The renal circulations. In The Kidney, Brenner, B.M., Rector, F.C., eds. Philadelphia: W.B. Saunders Company, pp 93–123.Google Scholar
- 2.Mimran, A. 1987. Regulation of renal blood flow. J Cardiovasc Pharmacol 10(Suppl 5):51–59.Google Scholar
- 11.Wolgast, M. 1968. Studies on the regional renal blood flow with labeled red cells and small beta sensitive semiconductor detectors. Acta Physiol Scand Suppl 31:1–109.Google Scholar
- 20.Cohen, H.J., D.J. Marsh, and B. Kayser. 1983. Autoregulation in the vasa recta of the rat kidney. Am J Phvsiol 245:F32–F40.Google Scholar
- 22.Stern, M.D., P. D. Bowen, R. Parma, R.W. Osgood, R.L. Bowman, and J. H. Stein. 1987. Measurement of renal cortical and medullary blood flow by laser-Doppler spectroscopy in the rat. Am J Phvsiol 236:F80–F87.Google Scholar
- 26.Roman, R.J., and C. Smits. 1985. Laser-Doppler determination of papillary blood flow in young and adult rats. Am J Physiol 251:F115–F124.Google Scholar
- 31.Roman, R.J., and E. Lianos. Influence of renal prostaglandins on papillary blood flow, renal interstitial pressure and the pressure natriuretic response. Hypertension 13, in press.Google Scholar
- 32.Thomas, C. E., and L.G. Navar. 1988. Influence of calcium channel blockade on the renal vasoconstrictive actions of platlet activating factor. Kidney Int 33:413.Google Scholar
- 34..Pollock, D.M., and W.J. Aredshorst. Tubuloglomerular feedback and blood flow autoregulation during DA1-induced renal vasodilation. Am J Physiol, in press.Google Scholar
- 37.Roman, R.J., A.W. Cowley Jr., J. Garcia-Estañ, and J. L. Lombard. 1988. Pressure-diuresis in volume-expanded rats: Cortical and medullary hemodynamics. Hypertension 12:168– 76.Google Scholar