Troponin I phosphorylation and myofilament calcium sensitivity during decompensated cardiac hypertrophy

Spontaneously hypertensive rats (SHR) are used to evaluate the myofilament calcium sensitivity-associated alteration in troponin-1 (Tn-1) phosphorylation and the expression of troponin isoforms during the evolution to decompensated cardiac hypertrophy. Results indicate that Tn-1 phosphorylation upon beta adrenergic stimulation of myocytes decreased among SHRs. The implications of these findings are discussed.