Renal | The Collecting Duct

Official Ninja Nerd Website: https://ninjanerd.org Ninja Nerds! In this renal physiology lecture, Professor Zach Murphy delivers a clear and in-depth breakdown of the Collecting Duct, the final segment of the nephron where the kidney fine-tunes water, sodium, potassium, hydrogen, and bicarbonate handling. This lecture builds on previous segments of the nephron and highlights the powerful role of hormones in regulating volume status, osmolality, and acid-base balance. We begin by outlining the distinct cell types within the collecting duct: principal cells, responsible for sodium reabsorption and potassium secretion under the influence of aldosterone, and intercalated cells, which regulate hydrogen and bicarbonate handling to maintain acid-base homeostasis. The role of aquaporins and ADH (vasopressin) is emphasized, showing how water permeability in the collecting duct becomes variable and tightly controlled based on hydration status. You’ll learn how the medullary concentration gradient, established by the loop of Henle, is critical for water reabsorption in the collecting duct when ADH is present. We also explore how aldosterone acts on principal cells by upregulating ENaC channels and the Na⁺/K⁺ ATPase, promoting sodium retention and potassium excretion. Enjoy the lecture and support us below! 🌐 Official Links Website: https://www.ninjanerd.org Podcast: https://podcast.ninjanerd.org Store: https://merch.ninjanerd.org 📱 Social Media   / ninjanerdlectures     / ninjanerdlectures     / ninjanerdlectures   https://x.com/ninjanerdsci/   / ninja-nerd   💬 Join Our Community Discord:   / discord   #ninjanerd #CollectingDuct #Renal