Elevation of Serum Soluble E- and P-Selectin in Patients with Hypertension Is Reversed by Benidipine, a Long-Acting Calcium Channel Blocker

Abstract

Hypertension is a major risk factor for atherosclerotic cardiovascular disease. Selectins, cell-surface adhesion molecules involved in leukocyte rolling and attachment to the vascular endothelium, play a role in the initiation of atherosclerosis. We investigated whether or not serum levels of soluble adhesion molecules are elevated in patients with essential hypertension (EH) and examined whether antihypertensive therapy lowers such levels. Twenty-one patients who had untreated mild to moderate EH without diabetes mellitus, hyperlipidemia, or obesity were recruited at a clinic for hypertensive patients. Blood pressure was measured, and the serum levels of soluble E-selectin, P-selectin, L-selectin, intercellular adhesion molecule 1 (ICAM-1), and vascular-cell adhesion molecule 1 (VCAM-1) were determined by enzyme-linked immunosorbent assays before and after 12, 24, and 53 weeks of antihypertensive treatment with benidipine, a long-acting calcium channel blocker, given at a dose of 6 mg/day for 53 weeks. As a control, 21 age- and sex-matched patients without hypertension were studied. Serum E- and P-selectin levels were significantly higher in the subjects with EH than in the controls (p < 0.01). There were no differences in serum levels of soluble L-selectin, VCAM-1, or ICAM-1 levels between the patients with EH and the controls. Treatment with benidipine decreased the elevated blood pressure over a 53-week study period (mean blood pressure: 119.8 +/- 6.5 mmHg at baseline, 101.0 +/- 5.9 mmHg at 12 weeks, 98.6 +/- 7.3 mmHg at 24 weeks, and 93.9 +/- 5.5 mmHg at 53 weeks). Serum levels of soluble E- and P-selectin decreased after the initiation of benidipine treatment and correlated with diastolic blood pressure. Serum levels of soluble L-selectin, VCAM-1, and ICAM-1 did not change significantly during the period of benidipine treatment. Benidipine treatment reduced the content of P-selectin in the platelets from patients with EH, as determined by Western blot analysis. In conclusion, decreased blood pressure may reduce the rate of progression of atherosclerosis by affecting the expression of E- and P-selectin in the endothelium, the platelets, or both. Benidipine may be protective against vascular damage in people with hypertension, not only by lowering blood pressure, but also by inhibiting the expression of selectins.