Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:2.3.1.21 (
CPT
)
4,580
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Hypertrophic cardiomyopathy (HCM) is associated with cardiac hypertrophy, diastolic dysfunction, and sudden death. Recently, it has been suggested that inefficient energy utilization could be a common molecular pathway of HCM-related mutations. We have previously generated transgenic Sprague-Dawley rats overexpressing a truncated cardiac troponin T (DEL-
TNT
) molecule, displaying typical features of HCM such as diastolic dysfunction and an increased susceptibility to ventricular arrhythmias. We now studied these rats using 31P magnetic resonance spectroscopy (MRS). MRS demonstrated that cardiac energy metabolism was markedly impaired, as indicated by a decreased phosphocreatine to ATP ratio (-31%, p < 0.05). In addition, we assessed contractility of isolated cardiomyocytes. While DEL-
TNT
and control cardiomyocytes showed no difference under baseline conditions, DEL-
TNT
cardiomyocytes selectively exhibited a decrease in fractional shortening by 28% after 1 h in glucose-deprived medium (p < 0.05). Moreover, significant decreases in contraction velocity and relaxation velocity were observed. To identify the underlying molecular pathways, we performed transcriptional profiling using real-time PCR. DEL-
TNT
hearts exhibited induction of several genes critical for cardiac energy supply, including CD36,
CPT
-1/-2, and PGC-1alpha. Finally, DEL-
TNT
rats and controls were studied by radiotelemetry after being stressed by isoproterenol, revealing a significantly increased frequency of arrhythmias in transgenic animals. In summary, we demonstrate profound energetic alterations in DEL-
TNT
hearts, supporting the notion that inefficient cellular ATP utilization contributes to the pathogenesis of HCM.
...
PMID:Decreased contractility due to energy deprivation in a transgenic rat model of hypertrophic cardiomyopathy. 1918 74