Premium
Impairment of Na + /H + exchange underlies inhibitory effects of Na + ‐free media on leukocyte function
Author(s) -
Nasmith Patricia E.,
Grinstein Sergio
Publication year - 1986
Publication title -
febs letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.593
H-Index - 257
eISSN - 1873-3468
pISSN - 0014-5793
DOI - 10.1016/0014-5793(86)80653-6
Subject(s) - chemistry , radiochemistry , function (biology) , isotopes of sodium , physics , sodium , biology , organic chemistry , evolutionary biology
Inhibition of activation has been reported when neutrophils are suspended in Na + ‐free media. We considered the possibility that impairment of cellular pH (pH i ) regulation due to elimination of Na + /H + exchange underlies this effect. In the absence of Na + , the phorbol ester‐induced respiratory burst was partially inhibited and a concomitant cytoplasmic acidification recorded. Using nigericin/K + to clamp pH i we demonstrated that the acidification accounts for the inhibition of O 2 uptake. Moreover, in Na + ‐free media, relieving the acidification by means of ionophores restored maximal O 2 consumption. It was concluded that Na + is not directly involved in signal transduction during stimulation. Instead, omission of Na + affects neutrophile activation indirectly, by impairing pH i regulation.