9. Distal Convoluted Tubule Explained | Thiazides, Calcium Reabsorption & RAAS | USMLE Step 1

𝐒𝐮𝐛𝐬𝐜𝐫𝐢𝐛𝐞 𝗙𝐨𝐫 𝗠𝐨𝐫𝐞 𝗜𝐧𝐟𝐨𝐫𝐦𝐚𝐭𝐢𝐨𝐧 𝐨𝐧 𝗛𝐞𝐚𝐥𝐭𝐡 👩‍⚕‍ 𝐚𝐧𝐝 𝗠𝐞𝐝𝐢𝐜𝐢𝐧𝐞💉🩺💊 📌𝗜𝗻𝘀𝘁𝗮𝗴𝗿𝗮𝗺 : https://www.instagram.com/clinical.learning/ Distal Convoluted Tubule Explained | Thiazides, Calcium Reabsorption & RAAS | USMLE Step 1 The Distal Convoluted Tubule (DCT), located in the renal cortex, plays a key role in fine-tuning electrolyte balance, acid-base regulation, and blood pressure control 🔄🩺. The early DCT is impermeable to water and actively reabsorbs Na⁺ and Cl⁻ via the Na⁺/Cl⁻ symporter, making it the target site for thiazide diuretics, which inhibit this transporter and increase natriuresis. Uniquely, the DCT is also the primary nephron segment responsible for active calcium reabsorption — stimulated by parathyroid hormone (PTH) — through apical TRPV5 channels and basolateral Na⁺/Ca²⁺ exchangers. In the late DCT and connecting tubule, aldosterone-sensitive principal cells regulate Na⁺ reabsorption and K⁺ secretion, contributing to RAAS-mediated blood pressure regulation. Intercalated cells in this region help manage acid-base balance by secreting H⁺ or HCO₃⁻ as needed. This segment also plays a pivotal role in urinary dilution before reaching the collecting duct. Dysfunction of the DCT is implicated in disorders like Gitelman syndrome, and its pharmacological manipulation is critical in hypertension and calcium stone prevention 💊🧪. #DistalConvolutedTubule #RenalPhysiology #USMLEStep1 #NEETPG #FMGEprep #DrSreeTeja #ThiazideDiuretics #PTH #CalciumReabsorption #RAAS #KidneyFunction #MBBSnotes #HighYieldPhysiology #MedStudentTips #NephronSimplified #InternalMedicine