BACKGROUND: Membrane structure in metabolic syndrome has not been fully investigated. The aim of our study was to determine the relationship between structural parameters of the erythrocyte membrane and blood pressure, indices of obesity, plasma lipids, and glucose levels in female patients with metabolic syndrome. MATERIAL/METHODS: In 23 women with metabolic syndrome and 12 control normotensive women, anthropometric indices, blood pressure, and serum lipids were evaluated and an oral glucose tolerance test was performed. Erythrocyte membranes obtained from these patients were investigated by electron spin resonance spectroscopy and the spin-labeling method. The order parameter S (membrane microviscosity), parameter h (index of membrane hydrophobicity), and the a/b ratio (index of the membrane surface configuration) were calculated. Data were analyzed using univariate correlation and stepwise multiple regression analysis. RESULTS: All membrane parameters differed significantly in women with metabolic syndrome from controls (P<0.001). The order parameter S was negatively related to waist circumference (R=-0.59, P<0.01) and positively to systolic blood pressure (R=0.44, P<0.05). Negative correlations of parameter h and the a/b ratio with postload plasma glucose level (R=-0.60 and -0.63, respectively, P<0.01) were observed. In stepwise multiple regression analysis the variation in the order parameter S was mainly explained by waist circumference and systolic BP (52%), and in parameter h and a/b ratio by postload glucose level (35% and 34%, respectively). CONCLUSIONS: Erythrocyte membrane structural changes in women are associated with features of metabolic syndrome, especially with abdominal obesity, high systolic blood pressure, and postload glucose level.
Med Sci Monit. 2005 Apr;11(4):CR203-10. Epub 2005 Mar 24.

OBJECTIVE: In previous studies, the I1 imidazoline specific agonist rilmenidine effectively lowered office blood pressure (BP) in patients with metabolic syndrome, improved glucose metabolism and did not demonstrate unfavourable effects on plasma lipids. The aim of the present study was to investigate the effects of 12weeks therapy with rilmenidine compared with the ACE inhibitor lisinopril on ambulatory BP, plasma lipid and fasting glucose levels in women with metabolic syndrome. RESEARCH DESIGN: Prospective randomised open-label, blinded end-points study. METHODS: Female patients (n = 51) with hypertension and other components of metabolic syndrome were treated with 1 mg rilmenidine (n = 24) or 10 mg lisinopril (n = 27), once- or twice-daily. Anthropometric measurements, office BP and heart rate (HR) measurements, ambulatory BP monitoring, lipid and fasting glucose assessment were performed before and after 12weeks of treatment MAIN OUTCOME MEASURES: Changes in ambulatory BP and HR, including 24-h, daytime and night-time values, and in lipids and glucose levels. All changes were adjusted for baseline values using the analysis of covariance method. RESULTS: Ambulatory 24-h systolic BP and diastolic BP were decreased significantly in the rilmenidine group (-11.9 +/- 1.9 and -7.7 +/- 0.8 mm Hg, p < 0.001) respectively and the lisinopril group (-11.0 +/- 1.8 and -6.7 +/- 0.7 mm Hg respectively, p < 0.001). There were no significant differences between the two groups. Rilmenidine reduced 24-h ambulatory HR (-3.6 +/- 0.8 bpm versus 0.3 +/- 0.8 bpm with lisinopril; p = 0.002). The reductions of day-time and night-time BP were also significant for both treatment groups, but the rilmenidine group demonstrated a greater decrease in night-time diastolic BP (p = 0.046). Rilmenidine significantly increased HDL cholesterol and decreased fasting glucose levels (p = 0.009 and p = 0.012, respectively). HDL cholesterol tended to increase and fasting glucose tended to decrease in the lisinopril group. However, differences between groups were not significant. Conclusion: Rilmenidine has similar effects on ambulatory BP patterns in hypertensive women with metabolic syndrome as lisinopril. Rilmenidine compared with lisinopril significantly reduces ambulatory HR. In this study, rilmenidine and lisinopril demonstrate similar effects on plasma lipid and fasting glucose levels.
Curr Med Res Opin. 2005 Jan;21(1):113-9.