Effect of Qing-Gan Yi-Shen Qu-Feng Formula on Blood Pressure and Thymus Morphology in Spontaneously Hypertensive Rats / 世界科学技术-中医药现代化

ABSTRACT

Spontaneously hypertensive rat (SHR) model was employed to investigate the effect of Qing-Gan Yi-Shen Qu-Feng (QGYSQF) formula on blood pressure and thymus morphology.SHR rats along with Wistar-Kyoto (WKY) rats were examined in parallel for changes in blood pressure and thymus morphology.SHR rats were treated with QGYSQF formula or antihypertensive drug.Candesartan was used as control.SHR and WKY rats treated with vehicle were included as controls for hypertension and normal blood pressure,respectively.Blood pressure was measured by tail cuff method in a non-invasive manner.Thymus weight was measured and morphological changes of thymus were observed by hematoxylin and eosin (HE) staining.The areas of thymus medulla and cortex were measured by image analysis software.The results showed that compared to that from the WKY rats,the blood pressure of SHR rats began to increase at 6 weeks of age.The systolic blood pressure of SHR rats was significantly elevated compared to that in WKY rats from 6 to 20 weeks of age (p ＜ 0.01).QGYSQF formula treatment resulted in significantly decreased blood pressure in SHR rats (p ＜ 0.01).Age-dependent atrophy was observed in SHR and WKY rats,which was evidenced by decreased weight of thymus.QGYSQF formula treatment resulted in significantly increased thymus index in 8-week old SHR rats compared to that from age-matched vehicle-treated SHR and WKY rats (p ＜ 0.01).Compared to that from WKY rats,the thymus atrophy of SHR rats progressed faster.Moreover,decreasing in areas of cortex and medulla and the blurring of medulla border were more evident in SHR rats.Compared to that from vehicle-treated SHR rats,QGYSQF formula treatment significantly increased the area of cortex as well as the total area of the thymus in 8-week old SHR rats (p ＜ 0.01).It was concluded that QGYSQF formula significantly attenuated the progression of hypertension in SHR rats.Meanwhile,QGYSQF formula treatment may exert protective effects on thymus when the blood pressure is elevated within a certain range or with shorter duration.