PSIO 532 Study Guide - Final Guide: Oncotic Pressure, Tubular Fluid, Capillary

• School: UNE
• Department: PSIO
• Course: PSIO 532
• Professor: Mueller

Document Summary

A reminder of the real anatomy of the nephron (see figure). We will simplify later for ease of conceptualization. Pc = hydrostatic pressure within the glomerulus, starts at 60 mmhg and decreases with distance. Ic = plasma colloid oncotic pressure, starts at 25 mmhg and increases with distance along the glomerular capillary (as protein-free fluid is filtered) Rt = tubular fluid oncotic pressure, normally nearly 0 mmhg. The arteriole-capillary-arteriole configuration permits higher hydrostatic pressures within the glomerular capillaries (compared with the typical capillary bed. Pc = 60 mmhg in glomerulus vs 40 at beginning of capillaries elsewhere). Notice that the plasma leaving the efferent arterioles and going into the peritubular capillaries thus has a lower hydrostatic pressure and a higher oncotic pressure. Again, we are going to be generalizing quite a bit. Be sure to remember that not all glomeruli and nephrons are identical. The superficial nephrons have lower gfr and shorter loops of henle than the juxtamedullary nephrons.