title: The effect of graded calcium infusions on rhythmic blood pressure oscillations in normal man.
abstract: This study was designed to determine whether calcium contributes to the regulation of rhythmic oscillations in blood pressure. Six normal subjects received sequential 1-h infusions of calcium gluconate (1.5, 3.0 and 4.5 mg calcium/kg/h) during continuous blood pressure (Finapres) monitoring. The plasma ionized calcium ([Ca2+]) concentration increased from 4.6 +/- 0.07 mg/dl to 5.97 +/- 0.20 mg/dl (p < 0.01) with infusion. The mid-frequency (0.07-0.14 Hz, Mayer wave) power spectrum of diastolic blood pressure was depressed slightly following the first dose but increased significantly following the final dose (p < 0.05). The high-frequency (0.15-0.40 Hz) power spectrum of systolic blood pressure decreased following the first dose (p < 0.05) and subsequently remained low. The low-frequency (0.02-0.6 Hz) power spectrum was not affected. These results demonstrate that graded hypercalcaemia affects blood pressure oscillations in man. Our data suggest that the amplitude of the Mayer wave, a clinical marker of sympathetic vascular tone, is modulated in part by calcium.
authors.affiliation: Second Department of Internal Medicine, Tohoku University, School of Medicine, Sendai, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Munakata
authors.forename: Y
authors.initials: Y
authors.lastname: Imai
authors.forename: K
authors.initials: K
authors.lastname: Mizunashi
authors.forename: J
authors.initials: J
authors.lastname: Hashimoto
authors.forename: H
authors.initials: H
authors.lastname: Sekino
authors.forename: Y
authors.initials: Y
authors.lastname: Furukawa
authors.forename: K
authors.initials: K
authors.lastname: Abe
mesh_terms: D000328:Adult; D001683:Biological Clocks / Q000187:drug effects*; D001794:Blood Pressure / Q000187:drug effects*; D002118:Calcium / Q000008:administration & dosage / Q000494:pharmacology*; D004562:Electrocardiography / Q000187:drug effects*; D006801:Humans; D007262:Infusions, Intravenous; D008297:Male
chemical_list: D002118:Calcium