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. 1993 Oct 1;295(Pt 1):317–320. doi: 10.1042/bj2950317

Cytoplasmic pH regulates ATP-induced Ca(2+)-dependent K(+)-current oscillation in rat megakaryocytes.

C Uneyama 1, H Uneyama 1, M Takahashi 1, N Akaike 1
PMCID: PMC1134856  PMID: 8216236

Abstract

The effect of cytoplasmic pH (pH(i)) on ATP-induced Ca2+ oscillation of rat megakaryocytes was investigated by the whole-cell patch-clamp technique. Megakaryocytes responded to extracellular ATP and showed the periodic activation of K+ channels, which reflects the oscillation in intracellular free Ca2+ concentration. Intracellular alkalinization by 20 mM NH4Cl resulted in inhibition of the oscillatory response, and intracellular acidification by 20 mM sodium acetate enhanced the response. NH4Cl also inhibited the Ins(1,4,5)P3-induced oscillation. Sodium acetate had no effect on the InsP3-induced oscillation, but enhanced the guanosine 5'-[gamma-thio]triphosphate-induced response. These results indicate that pH(i) modulates the ATP-induced cellular response at least at two points.

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Selected References

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