THE EFFECT OF PGI2 AND THEOPHYLLINE ON THE RESPONSE OF PLATELETS SUBJECTED TO SHEAR-STRESS

  • 1 January 1981
    • journal article
    • research article
    • Vol. 58  (4) , 678-681
Abstract
A specially designed rotational, viscometer was used to investigate the effects of the antiplatelet agent PG[prostaglandin]I2 in combination with theophylline on the response of human platelets subjected to shear stress. Samples of citrated platelet-rich plasma (PRP) were exposed to shear stress in the viscometer for a period of 5 min at 23.degree. C. The levels of stress studied ranged from 50-300 dyn/cm2. Pretreatment of the platelets with 0.01 .mu.M PGI2 and 500 .mu.M theophylline before exposure to shear stress caused a large reduction in shear-induced platelet aggregation. The PGI2-theophylline pretreatment concomitantly caused a large increase in shear-induced platelet lysis and serotonin release at stress levels .gtoreq. 150 dyn/cm2. This observed increase in platelet fragility may have important implications for clinical applications of PGI2. The results are discussed and compared to those obtained in prior work in which platelets were pretreated with acetylsalicylic acid or with PGE1.