ABSTRACT
The various effects of the endothelium derived hyperpolarizing functions (EDHFs) include possible interaction with the membrane Na K pump of vascular smooth muscle cells. While the fundamental ionic control mechanisms of the pump appear to be similar to its function in other cells, the actual number of functional pumps in the membrane of a given cell may vary. Thus when cells require an increase in membrane pumps, the initial response is the translocation of preformed pumps from a cytoplasmic pool. Drugs can also activate movement both to and from the membrane and pump content in the membrane is quite dynamic.
