• 1 January 1977
    • journal article
    • research article
    • Vol. 16  (4) , 735-743
Abstract
The injection of dibutyryl cyclic[c]AMP into the perfused rat heart resulted in dose-dependent increases in contractile force and phosphorylase a activity. In hearts from hyperthyroid animals both responses were markedly enhanced. The hyperthyroid state may produce changes in the heart making it more responsive to cAMP. Such a change could occur at the level of protein kinase. In hyperthyroidism, the heart may be more capable of taking up dibutyryl cAMP or of converting it to an active product.