Effects of gas bubbling and other forms of convection on platelets in vitro

of gas bubbling and other forms of convection on platelets in vitro. J. Appl. Physiol. 67(3): 1250~X255,1989.-Citrated plate-let-rich human plasma was subjected to one of three experi-mental treatments at 37°C for 15 min: stirring, bubbling (with stirring), and gentle agitation achieved by a rocking motion The last two were “equiconvective ” as judged by equilibration rates with CO2 and O2 but presumably differed in the shear stress they imposed on the cells. Stirring platelets in normal air or 5 % C02-air caused no significant aggregation. Bubbling air through platelet-rich plasma increased its pH and marked aggregation occurred. Bubbling C02-air caused the platelet-rich plasma pH to attain its physiological level of 7.4 with less aggregation. In both cases, subsequent ADP-induced aggrega-tion was diminished. Rocking (without stirring) in the presence of C02-air caused negligible aggregation in platelets and a