Background: Recently, it has been proposed that the autoantibodies against various cardiovascular receptors play a role in the pathogenesis of primary hypertension. In this study, we aimed to identify whether or not there are autoantibodies against cardiovascular L-type Ca2+ channels in patients with primary hypertension.
Methods: A peptide corresponding to the sequence 2-16 of the alpha1c-subunit of L-type Ca2+ channel was used as an antigen to screen the autoantibodies from 90 patients with primary hypertension and 45 healthy controls by an enzyme-linked immunosorbent assay (ELISA). The clinical data of 90 hypertensive patients were compared between patients with and without these autoantibodies.
Results: Serum from 3 (6.7%) of the 45 healthy controls, 33 (36.7%) of 90 hypertensives showed positive responses in ELISA (P < 0.01). The prevalence of such autoantibodies in two subgroups of hypertensives with coronary heart disease (9/21, 57.14%, P < 0.05) and left ventricular diastolic dysfunction (28/63, 44.4%, P < 0.05) was higher than in those without the corresponding complications. And the patients with such autoantibodies had lower E/A than patients without such autoantibodies (0.803 +/- 0.191 vs. 1.004 +/- 0.322, P = 0.002).
Conclusion: There are autoantibodies against vascular L-type Ca2+ channels in patients with primary hypertension.