Glomerular capillary pressure

Glomerular capillary pressure (PGC) is a hydrostatic pressure that pushes blood out of the capillary. The blood pressure in these capillaries is markedly different from that of typical capillaries. In capillaries elsewhere in the body, blood pressure at the arteriolar end is about 30 mmHg and at the venular end is about 10 mmHg (see Chapter 15). These pressures lead to the net filtration of fluid at the inflow end of the capillary and net reabsorption of fluid at the outflow end. 

Glomerular capillary pressure is determined primarily by renal blood flow (RBF). As RBF increases, PGC and therefore GFR increase. On the other hand, as RBF decreases, PGC and GFR decrease. Renal blood flow is determined by mean arterial pressure (MAP) and the resistance of the afferent arteriole (aff art) ... 

Haas JA, Osswald H. Adenosine Induced fall in glomerular capillary pressure effect of ureteral obstruction and aortic constriction in the Munich-Wistar rat kidney. Naunyn Schmiedebergs Arch Pharmacol 1981 317 86-89. 

Ang II preferentially constricts the efferent arteriole of the glomerulus, raising glomerular capillary pressure. 

Wilcox, C. S., Welch, W. J., Murad, F., Gross, S. S., Taylor, G., Levi, R., and Schmidt, H. FI. (1992). Nitric oxide synthase in macula densa regulates glomerular capillary pressure. Proc. Natl. Acad. Sci. U.S.A. 89, 11993-11997. 

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