Reduced GPIIb/IIIa expression in platelets hyposensitive to catecholamines when activated with TRAP.
BACKGROUND
A previous report assigned 35 healthy Koreans into five groups (groups A to E) based on their platelet responsiveness to catecholamines (CA). The present work aimed to elucidate the possible mechanism of heterogeneous responsiveness to CA in normal subjects.


METHODS
The degrees of aggregation in platelet rich plasma (PRP) were measured with a turbidimetric method. The expression of platelet glycoprotein and activation maker was analyzed with flow cytometric method in whole blood.


CONCLUSIONS
The degrees of aggregation in response to other aggregation inducing agents (AA, ADP, and U46619) were significantly lower in platelets hyporesponsive to CA. The flow cytometric analysis showed that GPIIb, GPIIIa and GPIIb/IIIa expressions were 20.1%, 25.7%, and 38.2%, respectively, higher in the CA-responsive group than in the CA-hyporesponsive group when the groups were in a TRAP activated state, while no differences were observed between the two groups when in a resting state.
Kim
Jeong Mi
JM
Natural Products Research Institute, College of Pharmacy, Seoul National University, Seoul 151-742, Korea.
Koo
Yean Kyoung
YK
Heo
Jung Eun
JE
Park
Seonyang
S
Yun-Choi
Hye Sook
HS
D000328:Adult; D001792:Blood Platelets / Q000187:drug effects / Q000378:metabolism*; D002395:Catecholamines / Q000378:metabolism* / Q000494:pharmacology; D005260:Female; D006801:Humans; D039661:Integrin beta3 / Q000378:metabolism*; D007723:Korea; D008297:Male; D008875:Middle Aged; D010446:Peptide Fragments / Q000494:pharmacology; D015539:Platelet Activation / Q000187:drug effects; D010974:Platelet Aggregation / Q000187:drug effects; D019039:Platelet Glycoprotein GPIIb-IIIa Complex / Q000378:metabolism*
D002395:Catecholamines; D039661:Integrin beta3; D010446:Peptide Fragments; D019039:Platelet Glycoprotein GPIIb-IIIa Complex; C086309:thrombin receptor peptide SFLLRNP