Studies on platelet plasma membranes. II. Characterization of surface proteins of rabbit platelets in vitro and during circulation in vivo using diazotized (125i)-diiodosulfanilic acid as a label.

摘要: Abstract Diazotized ( 125 I)-diiodosulfanilic acid (DD ISA) binds specifically to the exposed proteins on surface of rabbit platelet plasma membrane. This was demonstrated by following observations with use sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) whole platelets and isolated membrane fraction: (1) specific activity protein sevenfold that protein, (2) no intact were labeled which not represented in membrane, (3) DD ISA-labeled altered trypsin treatment intact, platelets, (4) pattern labeling produced reaction membranes ISA differed from platelets. Reaction only three glycoproteins (molecular weights: 180,000, 125,000, 92,000 daltons) greatest largest glycoprotein least smallest glycoprotein. When simultaneously 51 Cr, two isotopes similarly distributed various density populations Some solubilized washed sonication, but all recovered fraction after 30 minutes' circulation vivo. In vivo Cr recovery survival simultaneous ISA. The disappearance circulating (T12 = 17 hours) more rapid than appeared exponential contrast linear disappearance. On other hand, did disappear faster when doubly harvested 3 hours' incubated autologous elution=43 hours, 33 hours). SDS-PAGE analysis 14 20 same distribution as prior infusion. We interpret this symmetrical loss label indicate proteins, suggesting may lose pieces during circulation. could occur reversible adhesion encounters process hemostasis cause smaller size decreased effectiveness older