Abstract
Mouse resident peritoneal macrophages display sufficient 5'- nucleotidase activity to hydrolyze 58 nm AMP/min per cell protein. This activity increases approximately 163 nm AMP/min per mg after 72 h in culture. The enzyme is renewed in unstimulated cells with a half-time of 13.9 h. The activity is not reduced by treatment of intact cells with a variety of proteolytic enzymes, including trypsin, pronase, urokinase, and plasmin. Cells obtained from an inflammatory exudate have diminished or absent levels of enzyme activity. Endotoxin-elicited cells display enzyme activitiy of 20.9 nm AMP/min per mg, while thioglycollate-stimulated macrophages have no detectable activity. The reduced level of activity in endotoxin-stimulated cells is due to their elevated rate of enzyme degradation, with a half-time of 6.9 h. Their rate of enzyme synthesis is essentially normal. No evidence for latent enzyme activity could be obtained in thioglycollate-stimulated cells, nor do these cells produce any inhibition of normal cell enzyme activity. Serum deprivation reduces the enzyme activity of resident cells to about 45% of control activity. These conditions do not significantly affect the rate of enzyme synthesis, but again are explainable by an increase in the rate of enzyme degradation. Pinocytic rate is elevated in endotoxin-stimulated cells which show a more rapid rate of enzyme degradation than unstimulated cells do. However, in serum-free conditions, the rate of enzyme degradation is doubled with no change in the pinocytic rate of the cells.
Full Text
The Full Text of this article is available as a PDF (1.1 MB).
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Avruch J., Wallach D. F. Preparation and properties of plasma membrane and endoplasmic reticulum fragments from isolated rat fat cells. Biochim Biophys Acta. 1971 Apr 13;233(2):334–347. doi: 10.1016/0005-2736(71)90331-2. [DOI] [PubMed] [Google Scholar]
- Axline S. G., Cohn Z. A. In vitro induction of lysosomal enzymes by phagocytosis. J Exp Med. 1970 Jun 1;131(6):1239–1260. doi: 10.1084/jem.131.6.1239. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Berlin C. M., Schimke R. T. Influence of turnover rates on the responses of enzymes to cortisone. Mol Pharmacol. 1965 Sep;1(2):149–156. [PubMed] [Google Scholar]
- Bianco C., Griffin F. M., Jr, Silverstein S. C. Studies of the macrophage complement receptor. Alteration of receptor function upon macrophage activation. J Exp Med. 1975 Jun 1;141(6):1278–1290. doi: 10.1084/jem.141.6.1278. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Devreotes P. N., Fambrough D. M. Acetylcholine receptor turnover in membranes of developing muscle fibers. J Cell Biol. 1975 May;65(2):335–358. doi: 10.1083/jcb.65.2.335. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Edelson P. J., Cohn Z. A. 5'-Nucleotidase activity of mouse peritoneal macrophages. II. Cellular distribution and effects of endocytosis. J Exp Med. 1976 Dec 1;144(6):1596–1608. doi: 10.1084/jem.144.6.1596. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Edelson P. J., Cohn Z. A. Effects of concanavalin A on mouse peritoneal macrophages. I. Stimulation of endocytic activity and inhibition of phago-lysosome formation. J Exp Med. 1974 Nov 1;140(5):1364–1386. doi: 10.1084/jem.140.5.1364. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Edelson P. J., Zwiebel R., Cohn Z. A. The pinocytic rate of activated macrophages. J Exp Med. 1975 Nov 1;142(5):1150–1164. doi: 10.1084/jem.142.5.1150. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Gurd J. W., Evans W. H. Relative rates of degradation of mouse-liver surface-membrane proteins. Eur J Biochem. 1973 Jul 2;36(1):273–279. doi: 10.1111/j.1432-1033.1973.tb02910.x. [DOI] [PubMed] [Google Scholar]
- Hubbard A. L., Cohn Z. A. Externally disposed plasma membrane proteins. II. Metabolic fate of iodinated polypeptides of mouse L cells. J Cell Biol. 1975 Feb;64(2):461–479. doi: 10.1083/jcb.64.2.461. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kaplan J., Moskowitz M. Studies on the turnover of plasma membranes in cultured mammalian cells. II. Demonstration of heterogeneous rates of turnover for plasma membrane proteins and glycoproteins. Biochim Biophys Acta. 1975 May 6;389(2):306–313. doi: 10.1016/0005-2736(75)90323-5. [DOI] [PubMed] [Google Scholar]
- Karnovsky M. L., Lazdins J., Drath D., Harper A. Biochemical characteristics of activated macrophages. Ann N Y Acad Sci. 1975 Jun 13;256:266–274. doi: 10.1111/j.1749-6632.1975.tb36053.x. [DOI] [PubMed] [Google Scholar]
- LOWRY O. H., ROSEBROUGH N. J., FARR A. L., RANDALL R. J. Protein measurement with the Folin phenol reagent. J Biol Chem. 1951 Nov;193(1):265–275. [PubMed] [Google Scholar]
- Lay W. H., Nussenzweig V. Receptors for complement of leukocytes. J Exp Med. 1968 Nov 1;128(5):991–1009. doi: 10.1084/jem.128.5.991. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Schimke R. T. Control of enzyme levels in mammalian tissues. Adv Enzymol Relat Areas Mol Biol. 1973;37:135–187. doi: 10.1002/9780470122822.ch3. [DOI] [PubMed] [Google Scholar]
- Steinman R. M., Cohn Z. A. The interaction of soluble horseradish peroxidase with mouse peritoneal macrophages in vitro. J Cell Biol. 1972 Oct;55(1):186–204. doi: 10.1083/jcb.55.1.186. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Tweto J., Doyle D. Turnover of the plasma membrane proteins of hepatoma tissue culture cells. J Biol Chem. 1976 Feb 10;251(3):872–882. [PubMed] [Google Scholar]
- Unkeless J. C., Gordon S., Reich E. Secretion of plasminogen activator by stimulated macrophages. J Exp Med. 1974 Apr 1;139(4):834–850. doi: 10.1084/jem.139.4.834. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Werb Z., Cohn Z. A. Plasma membrane synthesis in the macrophage following phagocytosis of polystyrene latex particles. J Biol Chem. 1972 Apr 25;247(8):2439–2446. [PubMed] [Google Scholar]