Related Experiment Videos
Endogenous triacylglycerol utilization by the isolated rat atria
1Orientación Fisiología Humana, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, República Argentina.
Revista Espanola De Fisiologia
|March 1, 1988
Summary
Fasted rat atria utilized more stored fat (triacylglycerol/TG) for energy than fed rats. This fat mobilization supported atrial function, with insulin only regulating fat use in fed states.
Area of Science:
- Cardiovascular Physiology
- Metabolic Biochemistry
Background:
- Atrial function relies on energy substrates.
- The role of endogenous triacylglycerol (TG) in atrial energy metabolism is not fully understood.
Purpose of the Study:
- To investigate the mobilization of endogenous TG in isolated rat atria under different nutritional states (fasted vs. fed).
- To determine the influence of glucose and insulin on TG mobilization and atrial function.
Main Methods:
- Isolated rat atria from fasted and fed rats were incubated with glucose or a glucose-free medium containing 2-deoxyglucose.
- Triacylglycerol (TG) levels and atrial contractile/pacemaker activities were measured over 90 minutes.
- The effect of insulin on TG mobilization was assessed in fed atria.
Main Results:
- Fasted atria mobilized significantly more endogenous TG than fed atria.
- A mobilization-resistant TG pool was observed in fed atria.
- Greater TG mobilization in fasted atria correlated with better preservation of contractile and pacemaker activities.
- Insulin inhibited TG mobilization in fed atria with glucose but was ineffective in fasted atria.
Conclusions:
- Endogenous TG and glucose are important substrates for atrial function.
- Insulin regulates TG consumption primarily in the fed state.
- Enhanced TG mobilization in fasted atria contributes to meeting energy demands and maintaining atrial function.