PMID- 2169924
OWN - NLM
STAT- MEDLINE
DCOM- 19901119
LR  - 20210216
IS  - 0006-4971 (Print)
IS  - 0006-4971 (Linking)
VI  - 76
IP  - 8
DP  - 1990 Oct 15
TI  - Dependence of plasmin-mediated degradation of platelet adhesive receptors on 
      temperature and Ca2+.
PG  - 1546-57
AB  - The effects of activation of plasminogen by streptokinase and 
      tissue-type-plasminogen activator on platelet activation and the membrane 
      glycoproteins (GPs) that mediate platelet adhesion and aggregation are not yet 
      fully defined. To clarify effects on platelets during activation of plasminogen 
      in vitro, we used monoclonal antibodies (MoAbs), flow cytometry, and platelets 
      surface-labeled with 125I to characterize changes in receptors for fibrinogen 
      (GPIIb-IIIa), von Willebrand factor (GPIb), and collagen (GPIa-IIa). Activation 
      of plasminogen in plasma with pharmacologic concentrations of plasminogen 
      activators did not degrade GPIIb-IIIa or GPIb, and caused only a modest decrease 
      in GPIa. In washed platelets GPIIb-IIIa was extensively degraded by plasmin at 37 
      degrees C in the absence of exogenous Ca2+, conditions that destabilize the 
      IIb-IIIa complex. Degradation of GPIb in washed platelets displayed a similar 
      although less-marked dependence on temperature and the absence of Ca2+. The 
      binding of activation-specific MoAbs did not increase during activation of 
      plasminogen in plasma. We conclude that during pharmacologic fibrinolysis, 
      reported inhibition of platelet function in plasma is not due to degradation of 
      platelet-adhesive receptors. In addition, platelet activation observed during 
      thrombolytic therapy does not appear to be a direct consequence of plasminogen 
      activation.
FAU - Winters, K J
AU  - Winters KJ
AD  - Cardiovascular Division, Washington University School of Medicine, St Louis MO 
      63110.
FAU - Eisenberg, P R
AU  - Eisenberg PR
FAU - Jaffe, A S
AU  - Jaffe AS
FAU - Santoro, S A
AU  - Santoro SA
LA  - eng
GR  - HL-17646/HL/NHLBI NIH HHS/United States
GR  - HL-40506/HL/NHLBI NIH HHS/United States
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PT  - Research Support, U.S. Gov't, P.H.S.
PL  - United States
TA  - Blood
JT  - Blood
JID - 7603509
RN  - 0 (Antibodies, Monoclonal)
RN  - 0 (Iodine Radioisotopes)
RN  - 0 (Platelet Membrane Glycoproteins)
RN  - 0 (Receptors, Cell Surface)
RN  - 0 (Receptors, Collagen)
RN  - 0 (von Willebrand factor receptor)
RN  - 9001-91-6 (Plasminogen)
RN  - EC 3.4.- (Streptokinase)
RN  - EC 3.4.21.68 (Tissue Plasminogen Activator)
RN  - EC 3.4.21.7 (Fibrinolysin)
RN  - SY7Q814VUP (Calcium)
SB  - IM
MH  - Antibodies, Monoclonal
MH  - Calcium/*pharmacology
MH  - Enzyme Activation/drug effects
MH  - Fibrinolysin/*metabolism
MH  - Flow Cytometry
MH  - Humans
MH  - Iodine Radioisotopes
MH  - Plasminogen/metabolism
MH  - Platelet Adhesiveness/*drug effects
MH  - Platelet Membrane Glycoproteins/*metabolism
MH  - Receptors, Cell Surface/*metabolism
MH  - Receptors, Collagen
MH  - Streptokinase/pharmacology
MH  - Temperature
MH  - Tissue Plasminogen Activator/pharmacology
EDAT- 1990/10/15 00:00
MHDA- 1990/10/15 00:01
CRDT- 1990/10/15 00:00
PHST- 1990/10/15 00:00 [pubmed]
PHST- 1990/10/15 00:01 [medline]
PHST- 1990/10/15 00:00 [entrez]
AID - S0006-4971(20)75225-0 [pii]
PST - ppublish
SO  - Blood. 1990 Oct 15;76(8):1546-57.