The differences of platelet PAC-1, CD62P positive rates and serum platelet factor 4 levels in patients with large artery atherosclerotic stroke and cerebral small vessel disease

Abstract

Objective To investigate the differences of platelet membrane glycoprotein PAC-1 and CD62P expression in patients with cerebral small vessel disease and its subtype and large artery atherosclerotic stroke and to compare the traditional platelet activation markers and inflammatory chemokine platelet factor 4 （PF4）. Methods Peripheral blood platelet PAC-1,CD62P positive rates and serum PF4 concentration in 30 patients with large artery atheroscle- rotic stroke, 45 patients with cerebral small vessel disease and 30 controls were detected using flow cytometry and enzyme-linked irnmunosorbent assay. The differences between the groups were compared. Results The PAC-1, CD62P positive rates and serum PF4 concentration in the large artery atherosclerotic stroke group were 63.21% ± 9. 78%, 55.91% ± 8. 17%, and 30. 55 ± 15.56 ng/ml, respectively. They were significantly higher than 40. 65% ±17.42%, 36. 49%±14. 60%, and 12. 59 ± 5. 57 ng/mlin the cerebral small vessel disease group （all P = 0. 000）, and the latter was still higher than 13.55% ± 3. 14%, 9. 00% ± 2.32%, and 4. 95± 2. 82 ng/ml in the control group （all P = 0. 000）. There were significant differences in all the subtypes groups of cerebral small vessel disease between the PAC-1, CD62P positive rates and serum PF4 concentration. The leukoaraiosis with lacunar infarction group （n = 15; 47. 72%± 15.52%, 43.75%± 12.54%, and 13.96 ±5.23 ng/ml） and the simple lacunar infarction group （n = 15; 49. 87% ± 14. 65%, 43.98% ± 10. 55%, and 14. 41 ± 5.53 ng/ml） was significantly higher than the simple lacunar infarction group （n = 15; 24. 44%±8.45%, 21.74%±7. 19%, and 9. 40 ±4. 99 ng/ml） （P =0. 000, 0. 000, and 0. 013, respectively）. There was no significant difference between the former 2 groups （P = 0. 658, 0. 952, and 0. 858, respectively）. The peripheral blood platelet PAC-1 positive rate had significant correlation with CD62P positive rate in patients with ischemic cerebral disease （r = 0. 964, P = 0. 000）, and the serum PF4 concentration showed linier correlation with the PAC-1 （r =0. 846, P =0. 000） and CD62P （r = 0. 857, P =0. 000） positive rates. Conclusions The platelet membrane gtycoprotein PAC-1 and CD62P expression showed linear correlation, and they were consistent with the changes of PF4 concentration. This suggested that platelet activation and its mediated inflammatory mechanisms played an important pathophysiological role in the processes of atherosclerosis and thrombosis. This mechanism had sigrtificant difference between the different lesion types. Key words: Platelet membrane glycoproteins; P-selectin; Platelet factor 4; Stroke; Brain ischemia; Brain infarction; Atherosclerosis