Work

Phorbol myristate acetate stimulates ATP-dependent calcium transport by the plasma membrane of neutrophils.

Year: 1984

Type: article

Abstract: We studied the effect of phorbol myristate acetate (PMA) on the plasma membrane ATP-dependent calcium pump in neutrophils. Plasma membrane-enriched fractions ("podosomes") from PMA-stimulated guinea pig neutrophils exhibited a twofold stimulation of ATP-dependent calcium transport when compared with control podosomes. The stimulatory effect was rapid (beginning less than 2 min after exposure to PMA) and reached maximal values within 5 min. PMA increased the maximum velocity but not the affinity of the calcium pump for Ca++. Pump activation was not preceded by a rise in cytosolic free calcium concentration [Ca++]i, as assessed by the intracellularly trapped fluorescent calcium indicator Quin 2, but instead slightly lowered [Ca++]i and prevented the rise in [Ca++]i normally induced by the chemotactic peptide formyl-methionyl-leucyl-phenylalanine. These results suggest that the calcium pump in the plasma membrane of neutrophils may be stimulated by calcium-independent pathways, and that this activation could be one of the earliest events mediating some of the effects of phorbol esters.

Source: Journal of Clinical Investigation

DOI: 10.1172/jci111284

Authors: H Lagast, T Pozzan, F A Waldvogel, P D Lew

Institutions: University of Padua, Institut Jules Bordet, University Hospital of Geneva, Fondation Rose et Jean Hoguet

Language: English

Topic: Ion Channels and Receptors

Subfield: Sensory Systems

Field: Neuroscience

Domain: Life Sciences

SDG: Good health and well-being

Open Access status: bronze

Funders: National Science Foundation, Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung, Consiglio Nazionale delle Ricerche