Anti-embolic effect of Taorenchengqi Tang in rats with embolic stroke induced by occluding middle cerebral artery

Abstract

ObjectiveTo investigate the anti-embolic effect of Taorenchengqi Tang (TRCQT), a formulas from Traditional Chinese Medicine, plus aspirin in rats with embolic stroke induced by selective occlusion of the middle cerebral artery (MCA). Possible side effects of hemorrhagic incident and other bleeding events and anti-platelet effect were also explored. MethodsNinety rats were randomly separated into 9 groups (n = 10): group 1 a sham-operated group (n = 10); groups 2 and 3 orally treated with an isovolumetric solvent (distilled water) for 1 and 3 months, followed by thromboembolic occlusion (n = 10); groups 4 and 5 orally treated with aspirin (5 mg/kg) alone for 1 and 3 months, followed by thromboembolic occlusion (n = 10); groups 6 and 7 orally treated with TRCQT (0.5 g/kg) alone for 1 and 3 months, followed by thromboembolic occlusion (n = 10); groups 8 and 9 orally treated with TRCQT plus aspirin for 1 and 3 months, respectively followed by thromboembolic occlusion (n = 10). The ischemic stroke in rats was induced by selective MCA occlusion. One was orally administered. After the treatments, rats' brains were removed, sectioned and stained with triphenyltetrazolium chloride (TTC) for infarct volume measurement. The incidence of subarachnoid hemorrhage (SAH) and intracerebral hemorrhage (ICH) were observed. A potential gastric bleeding side effect was assessed by measuring hemoglobin (Hb), and prothrombin time (PT). Collagen-induced platelet activation and tail vein bleeding time were measured. ResultsTreatment with TRCQT alone or in combination with aspirin reduced infarct volume for 1 (P < 0.05), and 3 (P < 0.01) months without SAH and ICH incidences, and gastric bleeding. TRCQT treatment for 1 month was also not altered PT. Moreover, a concentration dependent inhibition of collagen-induced platelet activation, followed by increasing of tail vein bleeding time was observed after TRCQT treatment. ConclusionEither TRCQT alone or TRCQT plus aspirin exhibits potent neuroprotective effect by reducing infarct volume without changing the status of SAH, ICH and gastric bleeding possibly via inhibiting the platelet activation and increasing bleeding time.