Physiology 3120 Lecture Notes - Renal Function, Colloid, Solution

• School: Western University
• Department: Physiology
• Course: Physiology 3120
• Professor: Tom Stavraky

Document Summary

Filtrate that leaves the nephron (excretion) is the urine, made up of the processes listed above. Excretion = filtration reabsorption + secretion: pressures affecting glomerular filtration. Hydrostatic pressure of glomerular capillaries (pgc): pressure of blood flowing through glomerular capillaries; forces fluid out; about 55mmhg (biggest driving force of filtration) Colloid osmotic pressure of glomerular capillaries ( gc): pressure created due to presence of proteins; most proteins stay in glomerular capillaries; about -30mmhg. Hydrostatic pressure of bowman"s capsule (pbc): pressure of fluid already in bowman"s capsule; about -15mmhg. Colloid osmotic pressure in bowman"s capsule ( bc): pressure created due to presence of proteins in bowman"s capsule; but almost no protein in bowman"s capsule; about 0mmhg. Net filtration pressure = (pgc + bc) (pbc + gc) Net filtration pressure = pgc pbc gc. = 10mmhg normally (promotes filtration: glomerular filtration rate (gfr) Amount of fluid (with dissolved substances) that filters into bowman"s capsule per unit time.