Vitamin D deficiency reduces the inotropic effect of ouabain
Bazzani, C.; Arletti, R.; Bertolini, A.
Acta Vitaminologica et Enzymologica 5(3): 147-151
1983
ISSN/ISBN: 0300-8924 PMID: 6650301 Document Number: 199210
The inotropic effect of 10-6M ouabain was estimated in electrically stimulated ventricle strips from the heart of Wistar rats given a rachitogenic diet from 28 days old for 3 to 4 weeks. The force of contraction increased by 25.4% compared with 64.8% from ventricles of control rats given a normal diet and 55.8% in that of rachitic rats given cholecalciferol 1000 IU/kg daily subcutaneously for 5 days before removal of the heart. Basal isometric tension in ventricles was unaffected in controls and decreased in rachitic rats by decreasing calcium in the external solution from 3.66 to 1.83 mM. Results indicate that vitamin D is important for heart contractibility and for the activity of cardiac glycosides.