Total body sodium content determines extracellular fluid volume, and is regulated by the balance between sodium intake and sodium loss. Oubain is a poison that causes blockage of the Na+/K+ ATPase. Which of the following would occur after administration of oubain? Explain why?
a) Increased extracellular sodium concentartion
b) Increased intracellular potassium concentration
c) Increased cellular water concentration
d) increased intracellular chloride concentration
this question is confusing me. if the poison blocks the pump then basically na+ and k+ cannot move into and out of the cell. can any one explain it to me how would it increase any thing??
After administration of ouabain, the Na+/K+ ATPase pump is blocked, which means that sodium ions (Na+) cannot be actively transported out of the cell and potassium ions (K+) cannot be actively transported into the cell.
a) Increased extracellular sodium concentration: This is unlikely to occur because even though sodium cannot be actively transported out of the cell, it can still leak out passively through other channels, maintaining a relatively stable extracellular sodium concentration.
b) Increased intracellular potassium concentration: This is likely to occur because potassium is not being actively transported into the cell by the Na+/K+ ATPase pump and is therefore accumulating intracellularly.
c) Increased cellular water concentration: The administration of ouabain does not directly affect water concentration in cells. However, the imbalance in ion concentration caused by the blockage of the Na+/K+ ATPase pump may alter osmotic pressure and affect water movement, leading to potential changes in cellular water concentration. However, without more information, it is difficult to determine the specific outcome.
d) Increased intracellular chloride concentration: The administration of ouabain does not directly affect chloride concentration. The blockage of the Na+/K+ ATPase pump primarily affects the movement of sodium and potassium ions, not chloride ions. Therefore, intracellular chloride concentration is unlikely to increase due to ouabain administration.
In order to determine the effect of administering ouabain, let's understand the normal role of the Na+/K+ ATPase pump and how it affects the concentrations of sodium (Na+), potassium (K+), and water in and around cells.
The Na+/K+ ATPase pump, also known as the sodium-potassium pump, is responsible for maintaining the balance of sodium and potassium ions across the cell membrane. It actively transports three sodium ions out of the cell in exchange for two potassium ions being pumped into the cell. This process requires ATP (Adenosine Triphosphate) to provide energy.
Now, let's evaluate the possible effects of administering ouabain on the listed options:
a) Increased extracellular sodium concentration: Since ouabain inhibits the Na+/K+ ATPase pump, there would be a reduced ability to remove sodium from the extracellular fluid. This could result in an increased extracellular sodium concentration, as it would build up outside the cells.
b) Increased intracellular potassium concentration: With the Na+/K+ ATPase pump blocked, there would be a disruption in the normal potassium transport into the cells. This could lead to a buildup of potassium inside the cells, resulting in an increased intracellular potassium concentration.
c) Increased cellular water concentration: Oubain's direct effect is on the sodium-potassium pump, which primarily regulates ion concentrations and not water movement. Therefore, it is unlikely to directly cause increased cellular water concentration.
d) Increased intracellular chloride concentration: Oubain specifically blocks the Na+/K+ ATPase pump and does not directly affect chloride ions. Therefore, it is unlikely to cause increased intracellular chloride concentration.
To summarize, the most likely outcome after administering ouabain would be increased extracellular sodium concentration (option a) and increased intracellular potassium concentration (option b).