Enzymatic Regulation of the Sodium-Potassium Pump free essay sample

An investigation of enzymatic regulation of the sodium potassium pump in isolated skin of the frog, Rana Catesbiana. Electrochemical gradients are essential for biologic processes including but not limited to neuronal signaling, respiration, and osmoregulation. The Sodium-Potassium (Na/K) pump is one of the most well characterized structures for actively establishing these gradients. The current generated by the Na/K pump can be calculated by measuring the current required from an external source to bring the gradient (Voltage difference) created by the pump to zero. An increase in temperature has shown to increase the current generated by the Na/K pump with a slope of 12.5A/Co and a Q10 value of 1.72. Arginine vasotocin (AVT) also known as anti-diuretic hormone (ADH), acts to increase the activity of the enzyme regulated pump. At a constant temperature, a 10-fold increase in current was measured across the AVT treated skin in comparison to the baseline AVT absent skin preparation. We will write a custom essay sample on Enzymatic Regulation of the Sodium-Potassium Pump or any similar topic specifically for you Do Not WasteYour Time HIRE WRITER Only 13.90 / page The plasma membranes of cells contain pumps that drive out sodium from the cell and incorporate potassium into the cell. Physiologically, the blood plasma has a higher sodium concentration than the cytoplasm and conversely the cytoplasm has a highly potassium concentration than the plasma. Under these conditions, the Na/K pump is acting against a concentration gradient is therefore an active ATPase dependent process. Since the pump is under enzymatic regulation, we expect its activity to be governed by typical enzyme kinetics responding directly to changes in temperature and agents (such as hormones) that manipulate enzyme activity. It is also important to note that the Na/K pump pumps a net 3 Na+ ions out of the cell for every 2 K+ in. This creates a resting voltage potential across the membrane (1). The resistance of the channel allows for the net current across the pump to be measured indirectly by introducing an external voltage equal and opposite of the resting membrane potentia l created by the Na/K pump. Using the Ussing technique, a voltage clamp and Ohms law, we can derive the current generated by the Na/K pump under various conditions (2).