PMID- 11488939
OWN - NLM
STAT- MEDLINE
DCOM- 20010823
LR  - 20190910
IS  - 0902-4441 (Print)
IS  - 0902-4441 (Linking)
VI  - 66
IP  - 6
DP  - 2001 Jun
TI  - Modulators of intraplatelet calcium concentration affect the binding of 
      thrombospondin to blood platelets in healthy donors and patients with type 2 
      diabetes mellitus.
PG  - 396-403
AB  - Thrombospondin (TSP), which is secreted from alpha-granules of activated 
      platelets, binds to its surface receptor (CD36) in the presence of Ca2+. 
      OBJECTIVES: We monitored how the modulation of intraplatelet Ca2+ affects TSP 
      binding to CD36 on platelets from healthy donors and patients with type 2 
      diabetes mellitus. We also aimed to verify whether the impaired Ca2+ mobilisation 
      in diabetes influences TSP binding upon the pharmacological modulation of calcium 
      transport. METHODS: Whole blood cytometry was used to monitor TSP release/binding 
      and CD36 presentation in platelets from 28 type 2 patients and 33 healthy donors. 
      RESULTS: No significant changes in TSP and CD36 levels were revealed between the 
      groups in circulating platelets and TRAP-, collagen- or thrombin-activated 
      platelets. In healthy donors, 1 microM thapsigargin (TG) elevated the 
      TRAP-activated TSP binding (by up to 50%, p<0.001), 5 mM EGTA reversed the effect 
      (by up to 85%, p<0.001), and overcame the effect of TG when used together. Less 
      profoundly expressed effects occurred in the NIDDM group. In both groups TG 
      increased the presentation of CD36 in TRAP-stimulated platelets (p<0.05), whereas 
      EGTA lowered the TRAP-stimulated increase in CD36 (p<0.001). The inhibition of 
      CD36 by EGTA was stronger in healthy volunteers (41% vs. 32%, respectively, 
      p<0.05), whereas the activation by TG was higher in the NIDDM group (11% vs. 27%, 
      p<0.05). When acting together the suppressive effects of EGTA on TG-dependent 
      Ca2+ mobilisation were much attenuated in diabetic subjects (p<0.05). CONCLUSION: 
      Both the release of TSP and CD36 presentation are under the influence of agents 
      modulating intracellular Ca2+. Diabetic platelets seem more vulnerable to the 
      releasers of cytosolic [Ca2+] and more resistant to the blockers of cytosolic 
      [Ca2+] mobilisation.
FAU - Wieclawska, B
AU  - Wieclawska B
AD  - Laboratory of Haemostasis and Haemostatic Disorders, Medical University of Lodz, 
      Lodz, Poland.
FAU - Rozalski, M
AU  - Rozalski M
FAU - Trojanowski, Z
AU  - Trojanowski Z
FAU - Watala, C
AU  - Watala C
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - England
TA  - Eur J Haematol
JT  - European journal of haematology
JID - 8703985
RN  - 0 (CD36 Antigens)
RN  - 0 (P-Selectin)
RN  - 0 (Thrombospondins)
RN  - SY7Q814VUP (Calcium)
SB  - IM
MH  - Adult
MH  - Aged
MH  - Blood Platelets/drug effects/*metabolism
MH  - CD36 Antigens/drug effects/metabolism
MH  - Calcium/*metabolism
MH  - Diabetes Mellitus, Type 2/*blood
MH  - Female
MH  - Humans
MH  - Male
MH  - Matched-Pair Analysis
MH  - Middle Aged
MH  - P-Selectin/metabolism
MH  - Platelet Activation/drug effects
MH  - Protein Binding
MH  - Thrombospondins/drug effects/*metabolism
EDAT- 2001/08/08 10:00
MHDA- 2001/08/24 10:01
CRDT- 2001/08/08 10:00
PHST- 2001/08/08 10:00 [pubmed]
PHST- 2001/08/24 10:01 [medline]
PHST- 2001/08/08 10:00 [entrez]
AID - ejh466 [pii]
AID - 10.1034/j.1600-0609.2001.066006396.x [doi]
PST - ppublish
SO  - Eur J Haematol. 2001 Jun;66(6):396-403. doi: 
      10.1034/j.1600-0609.2001.066006396.x.