pump

[pump]

1. an apparatus for drawing or forcing liquid or gas.

2. to draw or force liquids or gases.

blood pump a machine used to propel blood through the tubing of extracorporeal circulation devices.

breast pump a pump for taking milk from the breast.

calcium pump the mechanism of active transport of calcium (Ca²⁺) across a membrane, as of the sarcoplasmic reticulum of muscle cells, against a concentration gradient; the mechanism is driven by hydrolysis of ATP.

enteral feeding pump an infusion pump specifically designed for administration of a solution through a feeding tube.

insulin pump see insulin pump.

intra-aortic balloon pump see intra-aortic balloon pump.

muscle pump compression of veins by the contraction of skeletal muscles, forcing blood towards the heart against the flow of gravity; seen particularly in the deep veins of the lower limbs. Called also venous pump.

Na⁺-K⁺ pump sodium-potassium pump.

proton pump a system for transporting protons across cell membranes, often exchanging them for other positively charged ions.

sodium pump (sodium-potassium pump) the mechanism of active transport driven by the energy generated by Na⁺,K⁺-ATPase, by which sodium (Na⁺) is extruded from a cell and potassium (K⁺) is brought in, so as to maintain the low concentration of sodium and the high concentration of potassium within the cell with respect to the surrounding medium. A high concentration of intracellular potassium is necessary for vital processes such as protein biosynthesis, certain enzyme activities, and maintenance of the membrane potential of excitable cells. Called also Na⁺-K⁺ pump.

stomach pump see stomach pump.

venous pump muscle pump.