title: Low density lipoprotein receptor-dependent prostaglandin synthesis in Swiss 3T3 cells stimulated by platelet-derived growth factor.
abstract: We studied the effects of human plasma lipoproteins on the synthesis of prostaglandin (PG) E2 in Swiss 3T3 mouse fibroblasts. Quiescent cells, maintained in medium deficient in both platelet-derived growth factor (PDGF) and lipoproteins, synthesized less than 8 ng of PGE2 per 10(6) cells per 22 hr, and this rate did not change in response to the addition of lipoproteins. In contrast, PDGF-stimulated cells, incubated in medium deficient in lipoproteins, synthesized 45-110 ng of PGE2 per 10(6) cells during the same period of time, and this rate increased 2- to 5-fold in the presence of added low density lipoproteins (LDL). This stimulatory effect of LDL seemed to depend on LDL receptor-mediated binding, uptake, and degradation of the lipoproteins because: both LDL and very low density lipoproteins were active, whereas high density lipoproteins were not; low concentrations of LDL were effective; the effect of native LDL was blocked by acetylation of the LDL; PDGF increased both the expression of LDL receptors and the cellular uptake of LDL; chloroquine blocked the effect of LDL but not that of exogenous arachidonic acid. These results provide evidence that the LDL pathway is critically linked to PG synthesis in PDGF-stimulated cells.
authors.forename: A J
authors.initials: AJ
authors.lastname: Habenicht
authors.forename: H A
authors.initials: HA
authors.lastname: Dresel
authors.forename: M
authors.initials: M
authors.lastname: Goerig
authors.forename: J A
authors.initials: JA
authors.lastname: Weber
authors.forename: M
authors.initials: M
authors.lastname: Stoehr
authors.forename: J A
authors.initials: JA
authors.lastname: Glomset
authors.forename: R
authors.initials: R
authors.lastname: Ross
authors.forename: G
authors.initials: G
authors.lastname: Schettler
mesh_terms: D000107:Acetylation; D000818:Animals; D016718:Arachidonic Acid; D001095:Arachidonic Acids / Q000494:pharmacology; D002460:Cell Line; D002738:Chloroquine / Q000494:pharmacology; D015232:Dinoprostone; D004705:Endocytosis / Q000187:drug effects; D007700:Kinetics; D008077:Lipoproteins, LDL / Q000378:metabolism / Q000494:pharmacology; D008079:Lipoproteins, VLDL / Q000494:pharmacology; D008247:Lysosomes / Q000502:physiology; D051379:Mice; D010982:Platelet-Derived Growth Factor / Q000494:pharmacology*; D011453:Prostaglandins / Q000096:biosynthesis*; D011458:Prostaglandins E / Q000096:biosynthesis; D011973:Receptors, LDL / Q000502:physiology*; D013329:Structure-Activity Relationship
chemical_list: D001095:Arachidonic Acids; D008077:Lipoproteins, LDL; D008079:Lipoproteins, VLDL; D010982:Platelet-Derived Growth Factor; D011453:Prostaglandins; D011458:Prostaglandins E; D011973:Receptors, LDL; D016718:Arachidonic Acid; D002738:Chloroquine; D015232:Dinoprostone