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The role of isoproterenol in the regulation of lipoprotein lipase (LPL) activity in adipose tissue and skeletal muscle was investigated in 25 normal healthy volunteers. Subjects were randomized to three infusion groups, one was saline and the other two consisted to different concentration of isoproterenol. Isoproterenol induced increases in plasma insulin levels, plasma glucose, free fatty acids, and glycerol but not muscle or adipose tissue LPL. It was suggested that isoproterenol may be involved in the regulation of LPL in muscle or adipose tissue.

Mice which were bred to produce abnormally high amounts of the glucose transporter GLUT-4 in their adipose tissue become obese because more glucose is used in making fatty acids than consumed as an energy source in muscles. These mice also exhibited an increase in the activity of lipoprotein lipase (LPL) in their adipose tissue, while LPL activity was less in their muscle tissues. These observations imply that the partitioning of glucose for energy use and fat deposition is altered in obesity.