An upward shift of intracellular pH rather than the final absolute pH value is critical for controlling gap junction permeability in tumor promoter-treated cells.
The tumor promoter TPA is found to inhibit gap junction permeability in monolayer cultures of hamster fibroblasts. This effect is associated with an increase in intracellular pH. Here we show that neither an increase in pHi alone nor TPA treatment under conditions preventing pHi-shift affect gap junction permeability. It is not the level of pHi reached, but rather the pHi-shift itself that is essential for the inhibition of gap junction permeability in the presence of TPA.
Budunova
I
I
A.N. Belozersky Laboratory of Molecular Biology and Bioorganic Chemistry, Moscow State University, USSR.
Mittelman
L A
LA
Margolis
L B
LB
D000818:Animals; D002478:Cells, Cultured; D006224:Cricetinae; D006863:Hydrogen-Ion Concentration; D007365:Intercellular Junctions / Q000187:drug effects*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*
D013755:Tetradecanoylphorbol Acetate