期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1981
卷号：78
期号：2
页码：732-736
DOI：10.1073/pnas.78.2.732
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Differentiation of 3T3-L1 fibroblasts to adipocyte-like cells was accompanied by a 19-fold increase in neutral triglyceride lipase activity, a 12-fold increase in diglyceride lipase activity, a 10-fold increase in monoglyceride lipase activity, and a 280-fold increase in cholesterol esterase activity. In contrast, acid acylhydrolase activities did not increase during differentiation. The rate of glycerol release from unstimulated intact cells increased by more than 1 order of magnitude upon differentiation. Isoproterenol (1 microM) and 1-methyl-3-isobutylxanthine (0.1 mM) further stimulated this rate of glycerol release 3-fold. The neutral triglyceride lipase activity in cell-free preparations of differentiated cells was activated 105% by cyclic AMP-dependent protein kinase. Neutral cholesterol esterase, diglyceride lipase, and monoglyceride lipase were also activated (117%, 10%, and 37+, respectively) by cyclic AMP-dependent protein kinase. In contrast, protein kinase had no effect on any of the four lysosomal acid acylhydrolase activities. Thus, hormone-sensitive lipase, the most characteristic and functionally important enzyme of adipose tissue, has been characterized in differentiated 3T3-L1 cells. The 3T3-L1 cell should be a valuable model system in which to study regulation of hormone-sensitive lipase, particularly its long-term regulation.
