Key result
Cultured adult ventricular myocytes rely primarily on fatty acids, with greater endogenous lipolysis than intact hearts.
Why the study?
The energy metabolism of exogenous and endogenous substrates in Ca-tolerant adult ventricular myocytes in short-term culture was investigated to understand substrate utilization.
Cultured adult ventricular myocytes rely primarily on fatty acids for energy, similar to intact myocardium, though endogenous lipolysis plays a larger role than in beating hearts.
Answers are grounded in this paper and cite their sources.
Replicates fatty acid preference of intact myocardium in cultured myocytes; leaves open whether higher endogenous lipolysis applies in vivo.
The energy metabolism of exogenous and endogenous substrates was investigated in Ca-tolerant adult ventricular myocytes in short-term culture. CO2 production from exogenous glucose (5 mM), lactate (5 mM), and palmitate (100 microM) were 8, 20, and 29 mumol X h-1 X g wet wt-1. Endogenous lipolysis shared in energy production by 78, 61, and 31%, respectively. Fatty acids represented the main respiratory fuel even when 10(-7) M insulin, 5 mM lactate, or 5 mM dichloroacetate were supplied in addition to glucose. With palmitate, triglyceride contents were doubled within 3 h of cell incubation. With 5 mM glucose as sole exogenous substrate the energy turnover in these resting cells resembled that of arrested hearts, corresponding to 2 ml O2 X min-1 X 100 g wet wt-1. It is concluded that the basic features of substrate metabolism resemble those of the intact myocardium in that fatty acids represent the major fuel, but the contribution of endogenous lipolysis is greater than in the beating heart.
No takes yet. Share an insight, caveat, or question.
Probst et al. (1986) studied Cultured adult cardiac myocytes. Exogenous substrates (glucose, lactate, palmitate) was evaluated on Energy metabolism (CO2 production and endogenous lipolysis contribution). In cultured adult ventricular myocytes, fatty acids represented the major respiratory fuel, with endogenous lipolysis contributing more to energy production than in the intact beating heart.
Synapse has enriched 10 related papers. Consider them for comparative context: