Blockade of sympathetic nervous system activity by rilmenidine increases plasma adiponectin concentration in patients with essential hypertension.

BACKGROUND

Adiponectin is an adipose tissue-specific protein with antiatherogenic and insulin-sensitizing properties. In patients with essential hypertension plasma adiponectin levels are lower than in healthy subjects. It is hypothetized that low plasma adiponectin concentration may be involved in the pathogenesis of vascular complications in hypertension. The aim of the study was to evaluate the effect of 6 months of antihypertensive therapy with rilmenidine on plasma adiponectin concentration in patients with essential hypertension.

METHODS

In 20 patients with essential hypertension (mean age 39 +/- 14 years; 11 F, 9 M; mean duration of hypertension 8 +/- 9 years) plasma adiponectin concentration (ELISA; B-Bridge International, San Jose, CA), insulin sensitivity (metabolic clearance of glucose-M value and M/plasma insulin ratio) by the euglycemic-hyperinsulinemic glucose clamp technique, and body fat content (DEXA) were estimated twice, before and after 6 months of antihypertensive monotherapy with rilmenidine (daily dose 1 to 2 mg).

RESULTS

The 6 months of treatment with rilmenidine resulted in a significant decrease of systolic (P = .007), diastolic (P = .002), and mean arterial blood pressure (P = .002), no significant change of body mass index (27.7 +/- 4.7 and 27.6 +/- 4.4 kg/m(2)), total body fat content (25.4 +/- 7.3 and 24.9 +/- 6.8 kg), and insulin sensitivity parameters (M value 6.0 +/- 2.5 and 5.8 +/- 4.3 mg/kg/min and M/plasma insulin ratio 7.4 +/- 5.0 and 6.9 +/- 4.3 mg/kg/min/mU/L). However after 6 months of treatment with rilmenidine a significant increase in plasma adiponectin concentration (from 12.5 +/- 6.1 to 16.9 +/- 11.1; P = .0002) was observed.

CONCLUSIONS

Antihypertensive therapy with rilmenidine correlates with an increase of plasma adiponectin concentration without any significant changes of insulin sensitivity and body fat content in patients with essential hypertension.