Comparative Effects Of Ramipril And Nitrendipine On Plasma Catecholamines In Different Risky Patients With Hypertension

Objective This study is to find out the levels of the plasma catecholamines(CAs) (norepinephrine, epinephrine) in different risky essential hypertension, the changes of catecholamines were observed between different intervals of ramipril and nitrendipine treatment(pre-treatment, one week post-treatment, three weeks post-treatment), and to investigate the influence to the plasma catecholamines after these two drugs' treatment, these two treatment efficiency were contrasted.Methods A randomized trial was performed in 60 patients with middle(M) to high(H) risky essential hypertension, the trial was assigned to ramipril group(group L) or nitrendipine group (group N), Group L (n=30) received oral ramipril tablets (5mg, 1/d) and Group N(n=30) received oral nitrendipine tablets(10~20mg, 3/d) for 3 weeks. 40 healthy subjects as control. Plasma samples were obtained at different intervals (pre-treatment, one week post-treatment, three weeks post-treatment). The levels of the plasma catecholamines were detected by high performance liquid chromatography-electrochemical detection. The relation between these indexs and the risky degree of essential hypertension was observed, and the influence to the indexs was also observed after one week's ^ three weeks' treatment, the efficiency of these two drugs was analyzed.Results 1. The levels of CAs in patients with middle or high risky hypertension were significantly higher than those in control group(P<0.05), and were increased with the clinical stages or severity of the diease(P<0.05). 2. The levels of CAs were postivelycorrelated with the value of MAP , male smoking family history(r=0.421, 0.413, 0.329, 0.399, 0.315, 0.324 , 0.458 , 0.397, P<0.05). 3. Ramipril could decreased the levels of CAs. For nitrendipine, the levels of CAs were decreased after 1 week's treatment, and the levels of CAs were increased after 3 weeks' treatment , but less than pre-treatment. 4. The total response rate of Ramipril group was 86.7% and 80% in nitrendipine group, no difference in the treatment efficiency(P>0.05), but ramipril had less adverse effect.Conclusion 1. The method of detecting the plasma catecholamines with high performance liquid chromatography was adapted for analyzing biological samples. 2. High sympathetic nervous activity was found in hypertension , the levels of the plasma catecholamines would be ascended with the risky degree of hypertension. 3. Ramipril could restrain the activity of sympathetic nervous system; Nitrendipine also could restrain sympathetic nervous activity, but the role was weak than ramipril. 4.Both ramipril and nitrendipine could decrese the blood pressure , there was no difference in the efficiency, but ramipril had less adverse effects than nitrendipine.