renal blood flow Flashcards
1
Q
explain the counter current system
A
- ascending limb = ions are pumped out of loop of henle. impermeable to water so water cant follow
- makes interstitium salty
- descending limb permeable to water so water moves out which conentrates the tubular fluid
- mechanism amplifies itself so more salt the interstitium the more water moving out
2
Q
what factors affect renal blood flow
A
autoregulation (reactive/protective)
RAAS
3
Q
why is controlling renal blood flow important
A
- to protect the nephron from high blood pressure
- to control GFR. renal blood flow and filtration are maintained even in states when the body is fluid deprived or dehydrated. this is important as it protects the body against worsening homeostatic imbalances
- RBF affects GFR which affects urine composition
