The target cells of aldosterone are in the:

Aldosterone is a mineralocorticoid hormone produced by the adrenal cortex. Its primary role is to regulate sodium and potassium balance, which in turn helps control blood pressure and fluid balance in the body. **Target Cells of Aldosterone:** - **Principal Cells of the Cortical Collecting Ducts in the Kidney:** - **Location:** These cells are located in the late distal tubule and the cortical collecting ducts of the nephron in the kidneys. - **Function:** Aldosterone acts on these principal cells to increase the reabsorption of sodium (Na⁺) and water into the bloodstream while promoting the excretion of potassium (K⁺) into the urine. This process helps maintain electrolyte balance and blood pressure. **Additional Target Tissues:** - **Colon:** Aldosterone also acts on the cells of the colon to promote sodium reabsorption and potassium excretion, which aids in maintaining overall electrolyte and fluid balance. - **Heart and Blood Vessels:** Although to a lesser extent, aldosterone can influence cardiac and vascular function, potentially contributing to cardiovascular health and disease. **Summary:** The primary target cells of aldosterone are the **principal cells located in the cortical collecting ducts of the kidney**. These cells play a crucial role in managing the body's sodium and potassium levels, thereby regulating blood pressure and fluid balance. **Reference:** - *Guyton and Hall Textbook of Medical Physiology* - *Berne & Levy Physiology* **Answer:** They act on principal cells in the kidney’s cortical collecting ducts (collecting duct cells).