The Countercurrent Theory 80 20130 >2. Countercurrent 3040 exchange逆流交换 50|60 60170 7080 20 80 80190 80 30 100 100 60 B
The Countercurrent Theory ➢ 2. Countercurrent exchange 逆流交换
2 Countercurrent exchange 300 mOSm/L Vasa rect Osm 2013O Blood flow 30140 ortex 0 sOlo Outer 6O|7O Medulla HO ono HO Inner Medulla l00 1 00
2. Countercurrent exchange
Maintenance of the osmotic Gradient in the medulla Vasa recta proximal tubule Bowmans dista capsule tubule blood (from renal blood Ito renal ein/ Filtration Reabsorption of actively pumped salt … Reabsorption of passively transported D Direction of flow loop of Henle x (to bladder/
Maintenance of the Osmotic Gradient in the Medulla Vasa recta
Maintenance of the osmotic Gradient in the medulla The vasa recta: Countercurrent exchanger 320 m Osm/L Recta n Osm/L Loop of henle CORTEX Blood flow Cortex HO H,0 500 700 HO Outer Medulla H,O 475m007o H,C . H,O 6251100 Urea Medulla Ho 1000 H,0 1200 Water transpon Soltite transport
Maintenance of the Osmotic Gradient in the Medulla ➢ The vasa recta: Countercurrent exchanger
Summary: Formation of concentrated or dilute Urine In the presence of ADH al fluid osmolality Collecting duct permeable m/g H,oI Corter to water> excretion of a concentrated urine In the absence of adh Collecting duct Nec impermeable to water> H excretion of a diluted urine
Summary: Formation of Concentrated or Dilute Urine In the presence of ADH Collecting duct permeable to water → excretion of a concentrated urine In the absence of ADH Collecting duct impermeable to water → excretion of a diluted urine