Lasix is a diuretic that blocks the reabsorption of sodium in the ascending loop of Henle. The result of giving this drug would be

Reduced extracellular fluids within the kidney, reduced blood pressure.

Explanation:

The loop of henle, which are located within the nephrons in the kidney, have a task of acquiring the water and NaCl from the blood and keeping enough of it in the body so that the homeostasis is maintained.

The result of giving Lasix that reduces the amount of NaCl reabsorption would first of all be "reduced extracellular fluids within the kidney" and it would also change the pH level of the blood and drop blood pressure levels.

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