Stabilizing role of platelet P2Y(12) receptors in shear-dependent thrombus formation on ruptured plaques.
BACKGROUND
In most models of experimental thrombosis, healthy blood vessels are damaged. This results in the formation of a platelet thrombus that is stabilized by ADP signaling via P2Y(12) receptors. However, such models do not predict involvement of P2Y(12) in the clinically relevant situation of thrombosis upon rupture of atherosclerotic plaques. We investigated the role of P2Y(12) in thrombus formation on (collagen-containing) atherosclerotic plaques in vitro and in vivo, by using a novel mouse model of atherothrombosis.


METHODS
Plaques in the carotid arteries from Apoe(-/-) mice were acutely ruptured by ultrasound treatment, and the thrombotic process was monitored via intravital fluorescence microscopy. Thrombus formation in vitro was assessed in mouse and human blood perfused over collagen or plaque material under variable conditions of shear rate and coagulation. Effects of two reversible P2Y(12) blockers, ticagrelor (AZD6140) and cangrelor (AR-C69931MX), were investigated.


RESULTS
Acute plaque rupture by ultrasound treatment provoked rapid formation of non-occlusive thrombi, which were smaller in size and unstable in the presence of P2Y(12) blockers. In vitro, when mouse or human blood was perfused over collagen or atherosclerotic plaque material, blockage or deficiency of P2Y(12) reduced the thrombi and increased embolization events. These P2Y(12) effects were present at shear rates >500 s(-1), and they persisted in the presence of coagulation. P2Y(12)-dependent thrombus stabilization was accompanied by increased fibrin(ogen) binding.


CONCLUSIONS
Platelet P2Y(12) receptors play a crucial role in the stabilization of thrombi formed on atherosclerotic plaques. This P2Y(12) function is restricted to high shear flow conditions, and is preserved in the presence of coagulation.
Nergiz-Unal
Reyhan
R
Department of Biochemistry, Cardiovascular Research Institute Maastricht, Maastricht University, Maastricht, The Netherlands.
Cosemans
Judith M E M
JM
Feijge
Marion A H
MA
van der Meijden
Paola E J
PE
Storey
Robert F
RF
van Giezen
J J J
JJ
oude Egbrink
Mirjam G A
MG
Heemskerk
Johan W M
JW
Kuijpers
Marijke J E
MJ
D000818:Animals; D050197:Atherosclerosis / Q000150:complications* / Q000473:pathology; D001777:Blood Coagulation; D002341:Carotid Artery Thrombosis / Q000473:pathology; D004195:Disease Models, Animal; D004617:Embolism / Q000209:etiology*; D018056:Hemorheology; D006801:Humans; D051379:Mice; D018345:Mice, Knockout; D010477:Perfusion; D058925:Receptors, Purinergic P2Y12 / Q000502:physiology*; D013927:Thrombosis / Q000473:pathology*
C548577:P2ry12 protein, mouse; D058925:Receptors, Purinergic P2Y12
Blood. 2009 Jul 23;114(4):881-90
19372258
N Engl J Med. 2009 Sep 10;361(11):1045-57
19717846
J Thromb Haemost. 2009 Sep;7(9):1556-65
19552634
J Am Coll Cardiol. 2006 Jan 3;47(1):155-62
16386680
J Thromb Haemost. 2004 Mar;2(3):476-84
15009466
Arterioscler Thromb Vasc Biol. 2007 Apr;27(4):728-39
17272754
Thromb Haemost. 2007 Mar;97(3):435-43
17334511
FASEB J. 2003 Apr;17(6):685-7
12586747
Circulation. 2009 Jan 6;119(1):116-22
19103996
Mol Pharmacol. 2003 Mar;63(3):639-45
12606772
Blood. 2007 Jun 15;109(12):5087-95
17311994
Thromb Haemost. 2009 Dec;102(6):1149-56
19967145
Arterioscler Thromb Vasc Biol. 2002 Apr 1;22(4):686-91
11950711
Atherosclerosis. 2005 Jul;181(1):19-27
15939050
Arterioscler Thromb Vasc Biol. 1999 Dec;19(12):3033-43
10591685
Blood. 2001 Dec 1;98(12):3340-5
11719372
Arterioscler Thromb Vasc Biol. 2003 Oct 1;23(10):1941-7
12933533
J Clin Invest. 2001 Jun;107(12):1591-8
11413167
J Atheroscler Thromb. 2003;10(5):267-74
14718743
Arterioscler Thromb Vasc Biol. 2007 Nov;27(11):2484-90
17761939
Thromb Haemost. 2005 Jun;93(6):1128-36
15968399
Blood. 2006 Nov 1;108(9):3045-52
16840732
Blood. 2004 Feb 15;103(4):1333-41
14563646
Cardiovasc Drug Rev. 2007 Winter;25(4):357-74
18078435
Arterioscler Thromb Vasc Biol. 2005 Dec;25(12):2673-8
16254207
Nat Med. 2002 Nov;8(11):1227-34
12411949
J Clin Invest. 2003 Aug;112(3):398-406
12897207
Thromb Haemost. 2008 Mar;99(3):466-72
18327393
J Thromb Haemost. 2008 Aug;6(8):1253-61
18513212
Pharmacotherapy. 2008 Oct;28(10):1233-42
18823219
Clin Cardiol. 2007 Dec;30(12):604-14
17847044
N Engl J Med. 2007 Nov 15;357(20):2001-15
17982182
Circulation. 2003 Aug 12;108(6):741-7
12885756
FEBS J. 2008 Jan;275(2):371-85
18081863
J Thromb Haemost. 2009 Jan;7(1):152-61
18983512
Blood. 2004 Apr 1;103(7):2585-92
14645014
FASEB J. 2005 May;19(7):825-7
15758040
Arterioscler Thromb Vasc Biol. 1999 Oct;19(10):2524-34
10521383
Arterioscler Thromb Vasc Biol. 1996 Jan;16(1):4-11
8548424
FASEB J. 2005 Jun;19(8):898-909
15923400