Question

3. Conn's syndrome is an endocrine disorder brought about by a tumor of the adrenal cortex that that causes excessive secretion of Aldosterone in an uncontrolled fashion. Based on what you know about the functions of Aldosterone, describe what changes will occur in the epithelial cells of the tubule in response to this increased aldosterone? What will be the resulting changes in plasma concentrations of these affected solutes from these changes?

Answer 1

1. * Functions of aldosterone

             * In kidney aldosterone enhance the reabsorption of sodium from the tubular fluid and

               increases excretion of pottasium and hydrogen irons through urine.

             * It prevent excess salt loss through sweating and secretion of saliva from salivary glands.

             * In intestine aldosterone promote the absorption of sodium.

             * It help to maintain normal blood pressure in the body through renin-angiotensin-aldosterone

               mechanism.

    * Changes occur in the epethelial cell in response to increased aldosterone

              * Aldosterone increases activity of basolateral membarine sodium-pottasium pump,

                 apical epethelial sodium channels and renal outer membarine pottasium channel

                (it transport pottasium out of the cells).

              * The above actions result increase sodium reabsorption and pottasium secretion.

              * It makes the lumen more electrically negative and result in chloride to follow sodium.

              * Along with sodium and chloride water will follow them by osmosis.

              * This changes result in increased extracellular sodium and fluid level and decrease in

                 extracellular pottasium level.

   * Changes in plasma concentration of solutes due to conn's syndrome or primary

   hyperaldosteronism.

                * It result in increased sodium and fluid level in extracellular tissues of the body and

                   reduced pottasium level leads to

                                     * Hypokalemia (low pottasium level).

                                     * Hypernatremia (excess sodium level).

                                     * Increase in plasma volume.

                                     * Metabolic alkalosis due to hypokalemia.

                                     * Metabolic alkalosis result in reduction of plasma ironic calcium level

                                        which leads to latent teany or frank tetany.

                                      * Hypokalemia result in suppression of release of insulin from pancreatic

                                         beta cells leads to impaired glucose tolerance.