title: The effects of high molecular weight hydroxyethyl starch solutions on platelets.
abstract: Physicochemical characteristics of hydroxyethyl starch (HES) molecules determine their side effects on hemostasis. Our aim in the present experiments was to test the antiplatelet effect of novel high molecular weight HES. Citrated whole blood was hemodiluted in vitro (0% and 20%) with either HES 550 (Hextend), HES 600 (6%Hetastarch-Baxter), HES 200 (Elohäst), or the solvent of Hextend in its commercially available solution. The availability of glycoprotein IIb-IIIa was assessed on nonstimulated and on agonist-induced platelets using flow cytometry. Glycoprotein IIb-IIIa availability increased significantly after hemodilution with Hextend and its solvent by 23% and 24%, respectively, but decreased in the presence of 6% Hetastarch-Baxter and Elohäst by 18% and 15%, respectively, with no significant difference between the latter two colloids. This study shows that Hextend does not inhibit platelet function as anticipated by its high molecular weight and degree of substitution. The unexpected platelet stimulating effect of Hextend is unique among the currently available HES preparations and may, at least in part, be induced by its solvent containing calcium chloride dihydrate (2.5 mmol/L). The platelet-inhibiting effect of 6%Hetastarch-Baxter was not significantly different from that of medium molecular weight HES 200.
authors.affiliation: Department of Anesthesiology and Intensive Care (B), Vienna Medical University, Austria.
authors.forename: Engelbert
authors.initials: E
authors.lastname: Deusch
authors.forename: Ulrich
authors.initials: U
authors.lastname: Thaler
authors.forename: Sibylle A
authors.initials: SA
authors.lastname: Kozek-Langenecker
mesh_terms: D000328:Adult; D001792:Blood Platelets / Q000187:drug effects* / Q000502:physiology; D054641:Dual Specificity Phosphatase 2; D005434:Flow Cytometry; D006438:Hemodilution; D006801:Humans; D006895:Hydroxyethyl Starch Derivatives / Q000494:pharmacology*; D008297:Male; D008970:Molecular Weight; D010446:Peptide Fragments / Q000494:pharmacology; D010975:Platelet Aggregation Inhibitors / Q000494:pharmacology; D019039:Platelet Glycoprotein GPIIb-IIIa Complex / Q000378:metabolism; D054648:Protein Phosphatase 2; D017027:Protein Tyrosine Phosphatases / Q000378:metabolism; D012996:Solutions
chemical_list: D006895:Hydroxyethyl Starch Derivatives; D010446:Peptide Fragments; D010975:Platelet Aggregation Inhibitors; D019039:Platelet Glycoprotein GPIIb-IIIa Complex; D012996:Solutions; C082835:thrombin receptor peptide (42-47); D054648:Protein Phosphatase 2; C517032:DUSP2 protein, human; D054641:Dual Specificity Phosphatase 2; D017027:Protein Tyrosine Phosphatases