Enhanced lipolysis during interaction of serum and adipose tissue: its mechanism and effect of starvation.
Addition of serum to incubated adipose tissue resulted in excess of free fatty acids and/or glycerol released. It was propranolol-resistant and in many but not all experiments greater after using serum of fasting (FS) rats than that of fed rats (CS). The increment of free fatty acids and/or glycerol released due to the presence of FS was not potentiated by theophylline; however the effect of both CS and FS was potentiated by heparin. The postheparin serum lacked the property of CS or FS. By the interaction with serum, adipose tissue could be substituted by lipoprotein lipase isolated either from this tissue or from bovine milk. It is suggested that the difference between CS and FS might be caused by a qualitative alteration of the lipoprotein pattern resulting in easier availability of serum lipids to the extraadipose tissues during starvation.
D000273:Adipose Tissue / Q000378:metabolism*; D000818:Animals; D004789:Enzyme Activation; D005230:Fatty Acids, Nonesterified / Q000378:metabolism; D005990:Glycerol / Q000378:metabolism; D008053:Lipid Mobilization; D008071:Lipoprotein Lipase / Q000378:metabolism; D008074:Lipoproteins / Q000097:blood* / Q000378:metabolism; D008297:Male; D051381:Rats; D013217:Starvation / Q000378:metabolism*
D005230:Fatty Acids, Nonesterified; D008074:Lipoproteins; D008071:Lipoprotein Lipase; D005990:Glycerol