Polymorphonuclear leukocyte membrane fluidity and cytosolic Ca(2+) content in young adults with acute myocardial infarction. Evaluation at the initial stage and after 12 months.
Our aim was to examine two aspects of polymorphonuclear leukocyte (PMN) rheology (membrane fluidity and cytosolic Ca2+ content), at baseline and after in vitro activation, in a group of young adults with acute myocardial infarction (AMI) at the initial stage and after 12 months. We enrolled 21 AMI subjects aged < or = 45 years (mean age 41.1 +/- 3.5 years) and evaluated PMN membrane fluidity, labelling intact PMN cells with the fluorescent probe 1,4-(trimethylamino)-phenyl-4-phenylhexatriene and the PMN cytosolic Ca2+ content marking PMN cells with the fluorescent probe Fura 2-AM, at baseline and after in vitro activation with 4-phorbol 12-myristate 13-acetate (PMA) and N-formyl-methionyl-leucyl-phenylalanine (fMLP). During the initial stage PMN membrane fluidity and cytosolic Ca2+ content did not distinguish AMI patients from control subjects; after 12 months, when compared with the initial stage, PMN cytosolic Ca2+ content was significantly increased. In vitro PMN activation with PMA and fMLP caused no variation of the two PMN parameters in control subjects, while in AMI patients membrane fluidity decreased and cytosolic Ca2+ content increased; the same behaviour pattern was observed after 12 months. The constant functional alteration of PMN cells in young AMI patients highlights the role of activated leukocytes as a component of the inflammatory reaction that follows ischemia.
Department of Internal Medicine, Cardiovascular and Renal Disease, Università di Palermo, Palermo, Italy.
G
G
Caimi
E
E
Hoffmann
B
B
Canino
M
M
Montana
F
F
Dispensa
E
E
Incalcaterra
M F
MF
Casciolo
A
A
Catania
R
R
Lo Presti
D000328:Adult; D002118:Calcium / Q000097:blood*; D002462:Cell Membrane / Q000502:physiology*; D003600:Cytosol / Q000378:metabolism; D005456:Fluorescent Dyes; D005500:Follow-Up Studies; D006801:Humans; D007958:Leukocyte Count; D008297:Male; D008560:Membrane Fluidity / Q000187:drug effects / Q000502:physiology*; D009203:Myocardial Infarction / Q000097:blood*; D009240:N-Formylmethionine Leucyl-Phenylalanine / Q000494:pharmacology; D018375:Neutrophil Activation / Q000502:physiology; D009504:Neutrophils / Q000187:drug effects / Q000502:physiology*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D013997:Time Factors
D005456:Fluorescent Dyes; D009240:N-Formylmethionine Leucyl-Phenylalanine; D013755:Tetradecanoylphorbol Acetate; D002118:Calcium