title: Effects of nafamostat mesilate on ADP-induced platelet aggregation and disaggregation in hemodialysis patients.
abstract: Nafamostat mesilate (NM), a synthetic protease inhibitor, is the most commonly used anticoagulant in the setting of extracorporeal circulation (ECC) in patients with bleeding tendency. It inhibits both platelet aggregation and activation of coagulation factors. Although it has been reported that NM disaggregates aggregated platelets, little is known about such an effect in the setting of hemodialysis therapy (HD). We examined the effects of NM on adenosine 5'-diphosphate (ADP)-induced platelet aggregation and disaggregation using platelet-rich plasma obtained from 6 HD patients. The platelet aggregation was stimulated by 3 microM ADP and change of aggregation was monitored by an aggregometer. NM adjusted to the final concentrations of 0.1 (1.9 x 10(-7)), 1.0 (1.9 x 10(-6)), 10, (1.9 x 10(-5)), and 100 (1.9 x 10(-4)) microg/ml (M) or veronal-buffered saline (VBS) as control was added before or after to the stimulation of ADP. NM not only inhibited platelet aggregation, but also disaggregated already aggregated platelets at concentrations of 1.0 microg/mln or higher. Moreover, NM almost completely disaggregated at 100 microg/ml. This NM concentration of 1.0 microg/ml was lower than the therapeutic concentration in ECC of HD (i.e., 10 M(-5)). Both inhibitory and disaggregatory effects of NM expressed a dose-related dependency. Our results suggest that NM can exert both aggregation inhibitory and disaggregatory effects on platelets of HD patients within the therapeutic concentration.
authors.affiliation: Laboratory of Cell and Gene Therapy, Institute for Advanced Medical Sciences, Hyogo College of Medicine, Nishinomiya, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Miyata
authors.forename: Toshiro
authors.initials: T
authors.lastname: Shirakawa
authors.forename: Bishnu
authors.initials: B
authors.lastname: Acharya
authors.forename: Shuji
authors.initials: S
authors.lastname: Terao
authors.forename: Akinobu
authors.initials: A
authors.lastname: Gotoh
mesh_terms: D000244:Adenosine Diphosphate / Q000037:antagonists & inhibitors* / Q000494:pharmacology; D001550:Benzamidines; D004305:Dose-Response Relationship, Drug; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D005112:Extracorporeal Circulation; D005260:Female; D006146:Guanidines / Q000494:pharmacology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010974:Platelet Aggregation / Q000187:drug effects*; D010975:Platelet Aggregation Inhibitors / Q000494:pharmacology; D006435:Renal Dialysis
chemical_list: D001550:Benzamidines; D004791:Enzyme Inhibitors; D006146:Guanidines; D010975:Platelet Aggregation Inhibitors; D000244:Adenosine Diphosphate; C032855:nafamostat