PubMed_ArguminSci  

PubMed:22467304 JSONTXT 8 Projects

Annnotations TAB TSV DIC JSON TextAE

Id Subject Object Predicate Lexical cue
T1 133-265 DRI_Background denotes Numerous studies have aimed to elucidate markers for the onset of decompensatory hypertrophy and heart failure in vivo and in vitro.
T2 266-438 DRI_Background denotes Alterations in the force-frequency relationship are commonly used as markers for heart failure with a negative staircase being a hallmark of decompensated cardiac function.
T3 439-750 DRI_Challenge denotes Here we aim to determine the functional and molecular alterations in the very early stages of compensatory hypertrophy through analysis of the force-frequency relationship, using a novel isolated muscle culture system that allows assessment of force-frequency relationship during the development of hypertrophy.
T4 751-871 DRI_Outcome denotes New Zealand white male rabbit trabeculae excised from the right ventricular free wall were utilized for all experiments.
T5 872-1205 DRI_Approach denotes Briefly, muscles held at constant preload and contracting isometrically were stimulated to contract in culture for 24 h, and in a subset up to 48 h. We found that, upon an increase in the preload and maintaining the muscles in culture for up to 24 h, there was an increase in baseline force produced by isolated trabeculae over time.
T6 1206-1287 DRI_Approach denotes This suggests a gradual compensatory response to the impact of increased preload.
T7 1288-1484 DRI_Approach denotes Temporal analysis of the force-frequency response during this progression revealed a significant blunting (at 12 h) and then reversal of the positive staircase as culture time increased (at 24 h).
T8 1485-1614 DRI_Background denotes Phosphorylation analysis revealed a significant decrease in desmin and troponin (Tn)I phosphorylation from 12 to 24 h in culture.
T9 1615-1750 DRI_Challenge denotes These results show that even very early on in the compensatory hypertrophy state, the force-frequency relationship is already affected.
T10 1751-1925 DRI_Background denotes This effect on force-frequency relationship may, in addition to protein expression changes, be partially attributed to the alterations in myofilament protein phosphorylation.