Antihypertension effect of astragaloside IV during cerebral ischemia reperfusion in rats

Stroke is one of the leading causes of death from diseases. When the blood supply to the brain tissue is interrupted, neuronal core death occurs due to the lack of glucose and oxygen in min. Blood pressure lowering after ischemic stroke was proven to be an effective strategy to achieve neurovascular protection and reduce the risk of recurrent stroke. Astragaloside IV is a pure small molecular compound isolated from Radix Astragali, and it is well documented that astragaloside IV has neuroprotective effect on cerebral ischemia reperfusion (CIR) injury through many mechanisms, including antioxidant, anti-inflammatory and anti-apoptotic. The present study adopted mean arterial pressure (MAP) monitoring, neurological scoring, 2,3,5-triphenyltetrazolium chloride staining, enzyme-linked immuno-sorbent assay, western blotting and other experimental methods to investigate the effect of astragaloside IV on systemic blood pressure during CIR in a middle cerebral artery occlusion animal model. It was demonstrated that astragaloside IV pretreatment significantly alleviated CIR injury as previously reported. In addition, the elevation of MAP during CIR was significantly inhibited by astragaloside IV administration. Moreover, it was revealed that the expression of Na(+)-K(+)−2Cl(−) cotransporter isoform 1 in the hypothalamus was inhibited and the subsequent synthesis of vasopressin was reduced by astragaloside IV pretreatment in the CIR animal model. In conclusion, astragaloside IV may alleviate CIR injury partially by lowering systemic blood pressure.