[Antithrombotic effects of molsidomine, isosorbide dinitrate and verapamil in a laser-induced thrombosis model].

Antithrombotic effects of molsidomine, isosorbide dinitrate and verapamil obtained from the Casela Riedel Pharma GmbH, Frankfurt/Main, Germany have been studied in the laser-induced rat thrombosis model. The investigations were carried out on male Wistar rats weighing 200-300 g. Thrombus formation was induced in small mesenteric arteries--25-35 microns diameter using argon laser. An interference contrast system based on a Leitz Orthoplan microscope for the evaluation of thrombus formation was used. The number of laser injuries needed to induce a defined thrombus proved to be a useful way to quantitate the results in this thrombosis model. All agents showed dose dependent antithrombotic effect in our laser model. Molsidomine and verapamil inhibited 30 min after single i.v. injection in minimal dose 1 mg/kg and in dose 5 mg/kg 2 hours after oral administration thrombus formation in small mesenteric arteries. Isosorbide dinitrate in higher doses: 10 mg/kg 30 min after i.v. injection and 20 mg/kg after oral feeding showed significant antithrombotic effect. Antithrombotic effect of administration of minimal effective doses of all agents lasted longer than 4 hours but less than 6 hours. All drugs in effective antithrombotic doses after intravenous injection showed also inhibitory effect on rat platelet adhesion to the siliconized glass and bovine subendothelial extracellular matrix.