Final answer:
Inhibiting the reabsorption of Na+ in the PCT most likely leads to a loss of vitamins and electrolytes, and can cause severe dehydration due to increased urine output. Loop diuretics working on the loop of Henle have a similar effect by preventing Na+ and Cl- reabsorption, leading to increased urination.
Step-by-step explanation:
If you took a drug that inhibited the reabsorption of Na+ in the Proximal Convoluted Tubule (PCT), a number of outcomes are possible, but based on the provided options, the most likely effect would be c) you would lose vitamins and electrolytes and could suffer severe dehydration. This is because Na+ reabsorption in the PCT is coupled with the reabsorption of water and other substances. When the reabsorption of sodium is inhibited, it leads to an osmotic diuresis effect, where more sodium and water remain in the tubular fluid and get excreted in urine, leading to increased urination which could result in dehydration.
Regarding the loop diuretics, they act on the ascending limb of the loop of Henle and inhibit Na+ and Cl- reabsorption. This inhibition leads to increased solute concentration in the tubule, which reduces the reabsorption of water later in the nephron and results in increased urine output. This is why one of the side effects is increased urination.