Related Research Between Endothelium-dependent Vasodilatation Function And Endogenous Digitalis-like Substance In Elderly Patients With Essential Hypertension

Objective: To observe the changes of flow–mediated– vasodilatation (FMD)of endothelium-dependent and nitroglycerin- mediated-vasodilatation(FMD)of endothelium-independent of brachial artery and plasma endogenous digitalis-like substance (EDLS) as well as the inter-relationships between FMD and EDLS in elderly patients with essential hypertension(EH)of group 1,group 2 and group 3.Methods : The study group consisted of 60 elderly patients with EH as EH subjects and 20 healthy elderly people as control subjects, The 60 EH patients were divided into three subgroups according to the level of blood pressure in accordance with the≤2005 Chinese Hypertension guidelines≥(n=20 in each group): EH1group,EH 2 group and EH 3 group. The level of endogenous digitalis-like substance in each study subject was determined, at the same time ,the endothelial function of their brachial artery was measured by using high-resolution ultrasonograhy. Applied for Ce1ermajer reference methods, all subjects were detected to vascular endothelial function. Measured separately for each subject at rest(D0),after reactive hyperemia(D1)and after sublingual nitroglycerin(D2)with brachial artery diameter.Flow-mediated vasodilatation(FMD)= (D1 - D0 ) /Do×100 % ; Nitroglycerin-mediated vasodilatation(NMD)=(D1 - D0 ) /Do×100 % . Results: 1. EDLS in elderly patients with EH are increasing the overall level, but the EH group no difference between men and women, controls, EH1 class group, EH2 class group, EH3 class EDLS plasma level group was gradually increased, and between the EH and the EH group compared with the control group separately EDLS plasma levels were also statistically significant differences exist (P <0.01). 2. Ultrasound test results showed that: (1) in basic conditions, there was no significant difference in the diameter of brachial arteries(Do) among the four experimental groups (P > 0.05); (2) Compared with each EH group,the diameter of brachial arteries after reactive hyperaemia (D1) in control group was significant increasing , and the diameter of brachial arteries after sublingual nitroglycerin (D2)was also significant increasing in all experimental groups , but their differences were not statistical significance (P >0.05). (3)Dysfunctions of vascular endothelium in the EH patients were more worse as the hypertension progressing. the level of brachial artery FMD was showed a progressive reduction between control group,EH1 group,EH 2 groups and EH3 group ,and their difference had statistical significance between each EH group and control group as well as among the three EH groups (P<0.01). However, there was no dramatically statistical significance in difference of NMD between each EH group and control group or among the three EH groups (P>0.05).(4)Correlative analysis showed FMD a significantly negative correlation with endogenous digitalis-like substance (r=-0.806, P<0.01).