“…The intracellular triglycerides are present as cytosolic lipid droplets (35) and membrane-bound particles (3), probably of lysosomal origin (5,8,9,38,39). Cell fractionation studies have revealed the presence of a lysosomal fraction enriched in triglycerides (1,19,34). Sevcral lipases have been demonstrated in heart tissue but the lipase responsible for basal and glucagonstimulated endogenous lipolysis is still a matter of dispute, although the inhibition of lipolysis in isolated perfused rat hearts in the presence of methylamine (11,12,22) and other lysosomotropic agents (8) favors a distinctive role of the acid lysosomal lipase in the lipolysis of endogenous triglycerides.…”