Phospholipid base exchange enzyme activity in sarcolemmal membranes from the heart of cardiomyopathic hamsters

Trimetazidine: potential mechanisms of action in hypertrophic cardiomyopathy

In this review we consider available information on the cardio- and cytoprotective properties and mechanism of action of trimetazidine, an antianginal drug. Two points in particular are addressed: the advantages of trimetazidine over classic drugs and its possible use for the long-term treatment of hypertrophic cardiomyopathy, described as an ischemic disorder.

Altered lipid metabolism in the failing heart of cardiomyopathic hamsters (UM-X7.1)

The lipid composition of different anatomic regions of 150 day-old UM-X7.1 cardiomyopathic hamster and age-matched controls (Syrian golden hamsters) was examined. Cardiomyopathic hamsters exhibit a phospholipid to protein ratio higher than healthy animals in atria, whereas the contrary is true in the other anatomic regions examined. In all tissues the cholesterol to phospholipid ratio is higher in cardiomyopathic hamster than in controls. Healthy and UM-X7.1 hamsters differ substantially as far as the percent distribution of fatty acids in total lipids is concerned, the lipids from cardiomyopathic animals accumulating fatty acids of the omega-6 series and being relatively poor in monoenoic fatty acids. The different fatty acid composition of heart lipids appears to be a consequence of a generalized disturbance of the lipid metabolism in cardiomyopathic hamsters during congestive heart failure.

Kinetic changes of ethanolamine base exchange activity and increase of viscosity in sarcolemmal membranes of hamster heart during development of cardiomyopathy

The activity of the phospholipid base exchange enzyme specific for ethanolamine has been measured in cardiac sarcolemmal membrane preparations from Syrian golden and UM-X7.1 cardiomyopathic hamsters. In Syrian golden hamsters, the Km of the enzyme for ethanolamine does not change with age, whereas it almost doubles in membranes from cardiomyopathic animals, from the 30th to the 150th day of age. During the same period, the membrane cholesterol content increases by 68% in cardiomyopathic hamsters, whereas it does not change significantly in the Syrian golden hamster strain. As a consequence, in the adult animal, the cholesterol to phospholipid ratio and the viscosity of sarcolemmal membranes are higher in UM-X7.1 strain than in Syrian golden hamsters. A cause-consequence relationship between the enzymatic changes and the compositional modifications in the sarcolemma occurring in UM-X7.1 hamsters during the development of cardiomyopathy is proposed.