The Pathogenic Machenism Of Homocysteine In The Type2Diabetes Mellitus With Salt-sensitive Hypertension

OBJECTIVE To explore the pathogenic machenism of homo cysteine in the type2diabetes mellitus (T2DM) with salt-sensitive hypertension, the inpatients in the groups of T2DM and T2DM with hypertension were given an acute oral normal saline test. By the results of the test, the ratio of salt-sensitive was detected in each groups and the change of the blood pressure affected by the normal saline and Lasix were observed. Meanwhile, the concentration of homocysteine and the activity of renin, angiotensin, aldosterone in serum were measured before and after the acute oral saline test.METHODS110diabetic inpatients were divided into two groups which was the group only T2DM (n=55) and the group T2DM with hypertension (n=55) from June2010to December2011. Healthy volunteers was a control group (n=56). The inpatients in the two diabetic groups haved drunk0.9%saline water500ml within10minutes in the morning, then30minutes later intaken furosemide20mg. The blood pressure which was taken for three times and gotten the average value in the inpatients were measured respectively before and30minutes later after drinking saline,1hour later after intaking Lasix. Meanwhile, the blood samples were taken before and30mins later after drinking saline and assessed for the concentration of homocysteine, the activity of renin, angiotensin, aldosterone and glycated hemoglobin with Radioim munoassay, Chemiluminescence, biochemical assessment.RESULTS1. Salt-sensitive patients ware23cases and the salt-sensitive ratio of41.8%in the group only T2DM. In the group T2DM with hypertension, salt-sensitive patients were30cases and the salt-sensitive ratio of54.5%.2. Whether the group T2DM or group T2DM with hypertension, the mean arterial pressure (MAP) in the salt-sensitive inpatients increased markedly after acute oral saline test (p<0.05), and decreased after furosemide (20mg) was taken (p<0.05). The MAP in the non salt-sensitive inpatients had no obvious changes either.3. After divided the salt-sensitive and non salt-sensitive in the group T2DM and the group T2DM with hypertension, the concentration of homocysteine in the groups salt-sensitive were higher than that in the groups non salt-sensitive before saline test. Comparison with group salt-sensitive, the concentration of homocysteine in the group T2DM with hypertension increased also than that in the group T2DM.4. The activity of renin, angiotensin I and aldosterone in all of the diabetic patients were significantly lower than that in control group (p<0.01) at baseline, the activity of renin, aldosterone in the groups salt-sensitive were lower than that in groups non salt-sensitive, no matter whether in the group T2DM or in the group T2DM with hypertension.5. The activity of renin and the concentration of angiotensin I (37℃) were sharply increased in the salt-sensitive group T2DM (p<0.01) after the cute oral saline test, while the concentration of homocysteine without obvious changes. In the salt-sensitive group T2DM with hypertension, the concentration of aldosterone and homocysteine and the activity of rennin also increased remarkablely (p<0.05), all this indexs decreased in that of groups non salt-sensitive. Comparison with salt-sensitive inpatients in the group T2DM, the activity of renin, aldosterone and homocysteine were higher in salt-sensitive inpatients in the group T2DM with hypertension, the levels of aldosterone and homocysteine were significantly increased (p<0.05).6. The concentration of homocysteine was positively correlated with the levels of plasma angiotensin Ⅰ (4℃) and (37℃)(r=0.379, p0.043; r=0.401, p=0.035) in salt-sensitive group T2DM with hypertension, and the relationship was not exist in groups non salt-sensitive.CONCLUSIONS1. The group T2DM as same as the group T2DM with hypertension existed the incidence of salt-sensitive, which was about50%.2. For the patients of T2DM with salt-sensitive hypertension, it may be a good choice to control the hypertension using sodium restriction and diuretics. But the poor results were showed for the patients of T2DM with non salt-sensitive hypertension.3. Homocysteine may participate in the pathogenesis becoming the salt-sens itivity hypertension in T2DM.4. No relationship was founded between RAAS and T2DM with non salt-sensitive hypertension.