4N1-1 can induce agglutination of fixed platelets.

(A) Untreated or fixed human platelets were stimulated with 25 μM 4N1-1, 50 μM 4NGG, and 50 μM 4N1K. Aggregation was monitored by light transmission. Arrow indicates addition of agonist. (B) Untreated or fixed human platelets were stimulated with 25 μM 4N1-1, 0.5 μg/mL convulxin, 0.1 U/mL thrombin, or 10 μg/mL vWF activated with 1 mg/mL ristocetin. After full aggregation, the platelets were fixed and the number of single platelets was determined. Results were expressed as a percentage of nonstimulated platelets. Triplicate samples from each donor were used, and means ± SD are shown. Aggregation results and single-platelet counts are from one experiment representative of 3. (C) Fixed and untreated platelets were simulated with 25 μM 4N1-1 and 10 μg/mL vWF activated with 1 mg/mL ristocetin, respectively. Aggregates were fixed and dehydrated for analysis by electron scanning microscopy. The white bar represents 10 μm.