[Antihypertensive effect and mechanism of Dendrobium officinale flos on high-blood pressure rats induced by high glucose and high fat compound alcohol].

This study aimed to investigate the antihypertensive effect and possible mechanism of Dendrobium officinale flos on hypertensive rats induced by high glucose and high fat compound alcohol. The hypertensive models were successfully made by high-glucose and high-fat diet, with gradient drinking for 4 weeks, and then divided into model control group, valsartan (5.7 mg·kg⁻¹) positive control group and D. officinale flos groups (3，1 g·kg⁻¹). After 6 weeks of treatment, the blood pressure of rats was measured regularly. After the last administration, endothelin-1 (ET-1), thromboxane B₂ (TXB₂), prostacyclin (PGI₂) and nitric oxide (NO) were tested. Endothelial nitric oxide synthase (eNOS) expression and lesion status in thoracic aorta were detected. The vascular endothelium dependent dilation of the thoracic aorta was detected by the isolated vascular loop tension test. The results showed that D. officinale flos could significantly reduce systolic blood pressure and mean arterial pressure in hypertensive rats, inhibit the thickening of thoracic aorta and the loss of endothelial cells, reduce plasma content of ET-1 and TXB₂, and increase the content of PGI₂ and NO. After long-term administration, vascular endothelium dependent dilation of the thoracic aorta was significantly increased, and could be blocked by the eNOS inhibitor (L-NAME) and increase the expression of eNOS. Therefore, D. officinale flos has an obvious antihypertensive effect on high glucose and high fat compound alcohol-induced hypertensive rats. Its mechanism may be correlated with the improvement of vascular diastolic function by protecting vascular endothelial cells, and finally resist hypertension.