VAMP-3 and VAMP-8, but not VAMP-2, are VAMP isoforms present in human platelets.

SDS lysate of brain tissue (50 μg; Clontech 7800-1, BD Biosciences, Palo Alto, CA), leukocytes (8 × 10³ leukocytes and 1 × 10³ platelets), and platelets (4 × 10⁷ platelets containing 4 × 10³leukocytes) (left panel) and rVAMP proteins (100 ng each; right panel) were analyzed by SDS-PAGE and immunoblotting. The membranes were probed with the indicated primary anti-VAMP antibodies. There were twice as many leukocytes in the leukocyte sample as in the platelet sample.