Ouabain is a specific inhibitor of the active transport of s

Ouabain is a specific inhibitor of the active transport of sodium ion out of the cell and is therefore a valuable tool in studies of membrane transport mechanisms. Which of the following processes in your own body would you expect to be sensitive to inhibition by ouabain? Explain each of your answers. a) Facilitated diffusion of glucose into a muscle cell. b) Uptake of potassium by red blood cells. c) Active uptake of lactose by the bacteria in your intestine.

Solution

Answer: Uptake of potassium ions by red blood cells

a) Facilitated diffusion of glucose into a muscle cell: it is not going to be affected by ouabian because glucose transport is mediated through facilitated diffusion in neurons but in normal musclls it required Na+ mediated gloucse cotransport but not facilitated diffusion

c) Uptake of potassium ions by red blood cells: it is possible sensitive to ouabian because it will affect Na⁺-K⁺ ATPase as a result high influx of Na+ & efflux of K+ finally causes reversible effects using the Na + /K + antiporter

d) Active uptake of lactose by the bacteria in your intestine: it is not sensitive to ouabian inhibition because it sugars transport in bacteria is relied upon proton (H +) gradient but not to sodium cotransport