Functional Effects of Hyperthyroidism on Cardiac Papillary Muscle in Rats.

Background: Hyperthyroidism is currently recognized to affect the cardiovascular system, leading to a series of molecular and functional changes. However, little is known about the functional influence of hyperthyroidism in the regulation of cytoplasmic calcium and on the sodium/calcium exchanger (NCX) in the cardiac muscle.

Objectives: To evaluate the functional changes in papillary muscles isolated from animals with induced hyperthyroidism.