Several Factors Contribute to the High GFR in the Human Kidney

The rate of plasma ultrafiltration in the kidney glomeruli (180 L/day) far exceeds that in all other capillary beds, for several reasons:

1) The filtration coefficient is unusually high in the glomeruli. Compared with most other capillaries, the glomerular capillaries behave as though they had more pores per unit surface area; consequently, they have an unusually high hydraulic conductivity. The total glomerular filtration barrier area is large, about 2 m2.

2) Capillary hydrostatic pressure is higher in the glomeruli than in any other capillaries.

3) The high rate of renal blood flow helps sustain a high GFR by limiting the rise in colloid osmotic pressure, favoring filtration along the entire length of the glomerular capillaries.

In summary, glomerular filtration is high because the glomerular capillary blood is exposed to a large porous surface and there is a high transmural pressure gradient.

Was this article helpful?

0 0
Essentials of Human Physiology

Essentials of Human Physiology

This ebook provides an introductory explanation of the workings of the human body, with an effort to draw connections between the body systems and explain their interdependencies. A framework for the book is homeostasis and how the body maintains balance within each system. This is intended as a first introduction to physiology for a college-level course.

Get My Free Ebook

Post a comment