GENETIC-CONTROL OF PLATELET ACTIVATION IN INBRED MOUSE STRAINS

Platelet activation in inbred mouse strains was studied using expressi on of P-selectin as a marker of activated platelets. P-selectin expres sion in response to no added stimulus (spontaneous activation) or in r esponse to adenosine diphosphate (ADP) and epinephrine or thrombin, wa s assessed using a flow cytometric assay. Wide variation in the respon siveness of different strains was observed with strains SJL and AKR in particular showing very high levels of spontaneous activation. Geneti c studies suggest that this phenomenon is under control of a small num ber of genes and that the same loci are probably responsible for the h igh activation of both SJL and AKR, Bone marrow transplant experiments show that the trait is expressed in the platelet itself. Screening of SWXJ and AKXD recombinant inbred lines suggests that one of the respo nsible genes is located on chromosome 3.