ABSTRACT
OBJECTIVE: To study the effect and action mechanism of the large plant Rhodiola Tablet on myocardial ischemia of rats. METHODS: Rat myocardial ischemia models were induced by coronary artery ligation. The levels of AST, ALT, CK and CK-MB in serum were observed, at the same time the expressions of B-raf, Ras and p-ERK1/2 in myocardial tissue were determined. RESULTS: The levels of AST, ALT, CK and CK-MB in rat serum, as well as the B-raf, Ras and p-ERK1/2 expression in rats myocardium in the large plant Rhodiola group were significantly lower than that in the model group. CONCLUSION: Large plant Rhodiola has a certain antagonism on myocardial ischemia injury in rats caused by coronary artery ligation. The mechanism of action may be related to the decreases in serum AST, ALT, CK and CK-MB, as well as myocardial high expression of the B-raf, Ras and p-ERK1/2.
ABSTRACT
To investigate the effects of ginkgolide A (GA), ginkgolide B (GB) and ginkgolide K (GK) on platelet aggregation in rabbits, and compare the similarities and differences among these three components. The effects of different doses of ginkgolide A, B and K on platelet aggregation induced by platelet activating factor (PAF) were observed by using in vitro experiment. The results showed that three compounds could inhibit platelet aggregation induced by PAF in vitro, and the intensity was GK> GB> GA. It was further found that all of them can mobilize [Ca2+]i and enhance intracellular c-AMP level in a dose-dependent manner, which was consistent to the ability to antagonize PAF receptor. These findings indicated that GK was highly selective for PAF receptor, and may inhibit platelet aggregation by activating cAMP signaling pathway and inhibiting intracellular [Ca2+]i mobilization; GB and GA also had strong antagonism to PAF receptor, but the effect was weaker than that of GK.
ABSTRACT
The left middle cerebral artery occlusion (MCAO) model was made by inserting the nylon thread plug into the internal carotid artery. The behavioral score, cerebral infarction area, brain water content, ethidium bromide (EB) spillover, coagulation four indices, occludin and MMP-9 expression in brain tissues were detected after 14 days of administration, to investigate whether the protective effect of ginkgo diterpene lactone meglumine injection (GDLMI) which had obvious protective effect on cerebral ischemic injury in the previous experiment was related to reducing the permeability of the blood-brain barrier (BBB) and reducing the risk of bleeding, and to explore its possible mechanism of action. The results showed that GDLMI could effectively alleviate the behavioral changes caused by MCAO at 24 h, reduce the behavioral score, improve the edema of brain tissue, reduce the EB overflow rate, reduce the bleeding tendency caused by long-term administration, significantly reduce the occlusion deficiency in ischemic brain tissue of model rats, and down-regulate MMP-9 expression. The above results indicate that GDLMI has obvious effect on cerebral ischemia, and the therapeutic effect of GDLMI may mainly depend on lowering the permeability of blood-brain barrier to improve brain edema.
ABSTRACT
Objective: To investigate the effects of Tongsaimai Prescription (TSMP) and TSMP without Achyranthis Bidentatae Radix (ABR) on ischemic brain injuries in rats. Methods: The male SD rats were divided into Sham, model, Nimodipine (32.4 mg/kg), TSMP (crude drug 31.74 g/kg), and TSMP without ABR (crude drug 27.77 g/kg) groups. Except the Sham and model groups, the rats were ig administered once daily, for 3 d. After the treatment, except the Sham group, the cerebral ischemic stroke model was established. After 24 h, the blood and brain tissue were taken, the brain tissue was stained with TTC, and the cerebral infarction ratio was measured. The pathological changes were observed, and the contents of HMGB1, TNF-α, and IL-1β in serum were detected. The expression of NF-κB in ischemia tissue was observed by immunohistochemisty method. Results: The expression of HMGB1, TNF-α, and IL-1β increased obviously (P < 0.05). TSMP and TSMP without ABR could decrease the contents of HMGB1, TNF-α, and IL-1β, inhibit the expression of NF-κB (P < 0.05), and the effect of TSMP without ABR on decreasing IL-1β was stronger. Conclusion: Both TSMP and TSMP without ABR could inhibit the activation of HMGB1-related NF-κB signal pathway with the function of anti-imflammation, alleviated encephaledema, and protecting nerve cells. TSMP without ABR has the similar effect on the ischemic brain injuries and the better effect on inhibiting the secretion of inflammatory factor IL-1β.