Effects of Antiplatelet Agents in the Prevention of Ventricular Tachyarrhythmias during Acute Myocardial Ischemia in the Rats

Abstract

Background Aspirin, one of the antiplatelet agents, improves the survival rate after myocardial infarction. This beneficial effect is known to be obtained in part by the antiarrhythmic action of aspirin. It is not known whether other antiplatelet agents have such effects. This study was performed to compare the effects of aspirin, ticlopidine, and abciximab platelet glycoprotein IIb/IIIa receptor antagonist on the ischemia-induced arrhythmias with a rat model of cardiac regional ischemia. Methods Experiments were performed in 4 groups of rats. The 4 groups were as follows control, n 10 aspirin-pretreated, 300 mg/kg po for 1 week ticlopidine-pretreated, 200 mg/kg po for 1 wk abciximab-pretreated, 2 mg/kg iv 10 20 minutes before experiment. The electrocardiogram and blood pressure were recorded during 20 minutes. The time to the onset of ST-segment elevation and ventricular tachyarrhythmias, frequency and incidence of ventricular tachyarrhythmias, and death rate were assessed during acute myocardial ischemia induced by ligation of proximal left anterior descending coronary artery in anesthetized rats. Results Platelet aggregations to ADP were significantly lower in aspirin 42.8% , ticlopidine 43.8% , and abciximab group 34.0% than in control group 66.4% . The frequencies of sustained ventricular tachycardia VT were 6.8 3.6 in control, 3.6 3.8 aspirin, 4.7 3.7 ticlopidine, and 1.4 2.5 abciximab group. The frequency of sustained VT in the abciximab group was significantly lower than in control group. The incidences of ventricular arrhythmias for 20 min were 10/10 for VT and 8/10 for ventricular fibrillation VF in control group, 7/10 for VT and 3/10 for VF in aspirin group, 10/10 for VT and 3/10 for VF in ticlopidine group, and 5/10 for VT and 4/10 for VF in abciximab group. The incidences of cardiac death during 20 min were 8/10 in control group, 4/10 in aspirin group, 2/10 in ticlopidine group and 5/10 in abciximab group. The incidence of VT in the abciximab group was significantly lower than in control group, incidences of VF in the aspirin and ticlopidine groups were significantly lower than in control group, and death rate in ticlopidine group was significantly lower than in

Effectiveness of antiplatelet drugs against experimental non-alcoholic fatty liver disease

“…The G1–G4 groups were given the CDAA diet throughout the experimental period, and the G5 group was given the CSAA diet. In addition to the diet, the G2 group was administered oral aspirin once a day at a dose of 150 mg/kg/day,8 the G3 group was administered oral ticlopidine once a day at a dose of 100 mg/kg/day,9 and the G4 group was administered oral cilostazol once a day at a dose of 100 mg/kg/day 10…”

Experimental pulmonary embolism: Effects of the thrombus and attenuation of pulmonary artery injury by low-molecular-weight heparin

“…Doses of the various treatment agents were derived from the available literature. [12][13][14] No treated rats died from hemorrhagic complications. Control rats (n ϭ 61) were injected with an equivalent volume of normal saline either subcutaneously or in the dorsal tail vein, as appropriate.…”

Trapped Platelets Activated in Ischemia Initiate Ventricular Fibrillation

“…Pretreatment with aspirin, ticlopidine, meclofenamate, or indomethacin reduced ischemia-induced VF incidence from a high baseline in anesthetized rats. 15,16 However, aspirin failed to reduce ischemia-induced VF in conscious rats with a large IZ. 30 Likewise, platelet-activating factor antagonists ameliorated ischemia-induced VF in vivo in 2 study, 31 but not in others.…”

“…Moreover, aspirin pretreatment reduced ischemia-induced VF in various animal models. [15][16][17] However, there is a lack of evidence directly linking anti-VF effects to platelet ablation. It has been argued that a systematic examination of the role of platelets in VF initiation during ischemia is long overdue.…”