WP5085 - Vasopressin-regulated water reabsorption - Homo sapiens

This pathway describes Vasopressin-regulated water reabsorption from the kidney tubules of the nephrons back into the circulation. Vasopressin, antidiuretic hormone (ADH), is a peptide hormone produced in neurons of the hypothalamus in response to changes in response to extracellular fluid hypertonicity (hyperosmolality), and is secreted into the circulation. When it reaches the kidney, it binds to Vasopressin 2 receptors, triggering an intracellular signaling cascade that ultimately leads to aquaporin 2 (AQP2) vesicles inserted in the apical membrane. This increases the water permeability of the membrane. An osmotic gradient then drives water transport from the collecting duct through AQP2, and water exits the cell on the basolateral side, and back into the circulation. This description was adapted from [Wikipedia](https://en.wikipedia.org/wiki/Vasopressin) and [KEGG](https://www.genome.jp/entry/pathway+map04962). This pathway was modeled from [KEGG](https://www.genome.jp/entry/pathway+map04962).