title: Mechanical stress activates platelets at a subhemolysis level: an in vitro study.
abstract: A feasibility study is performed to quantify sheep platelets (PLTs) and to identify the relationship between PLT count and hemolysis as a consequence of mechanical stress. Six adult, healthy Dorset sheep have been used for in vitro blood sampling test procedures in a hemoresistometer device (HRM). In each experiment, blood of the same animal was exposed to six different shear rates. Free hemoglobin levels and PLT count for each shear rate were detected. In all animals (A-F), hemolysis increased significantly between the shear rates of 2325 and 3100/s (P < 0.05) and the mean PLT count dropped immediately (contact, low shear) 40% in the beginning, between the shear rates of 0 and 775/s (P < 0.05). PLT count increased slightly as soon as hemolysis started. At higher shear rates, hemolysis increased and PLTs reduced further. Precise counting of PLTs indicates that PLTs are consumed dramatically at very low shear (by contact) and further by applied mechanical stress when hemolysis is obvious. A repetition of these tests with human blood could indicate species differences.
authors: Center for Experimental Surgery and Anesthesiology, Cardiovascular Research Unit, Catholic University of Leuven (KUL), Leuven, Belgium. ihsanbak@yahoo.com
authors: Ihsan
authors: I
authors: Bakir
authors: Marc F
authors: MF
authors: Hoylaerts
authors: Thomas
authors: T
authors: Kink
authors: Luc
authors: L
authors: Foubert
authors: Peter
authors: P
authors: Luyten
authors: Soetkin
authors: S
authors: Van Kerckhoven
authors: Veerle
authors: V
authors: Leunens
authors: Hilde
authors: H
authors: Bollen
authors: Helmut
authors: H
authors: Reul
authors: Bart
authors: B
authors: Meyns
mesh_terms: D000818:Animals; D001792:Blood Platelets / Q000166:cytology* / Q000502:physiology*; D005240:Feasibility Studies; D006454:Hemoglobins / Q000032:analysis; D066298:In Vitro Techniques; D015539:Platelet Activation; D010976:Platelet Count; D033081:Shear Strength; D012756:Sheep; D013314:Stress, Mechanical
chemical_list: D006454:Hemoglobins