Stimulation of Human Smooth Muscle Cell Proliferation by Thrombin Involves Increased Synthesis of Platelet-Derived Growth Factor

• Published in: Chest Vol. 114; no. 1; pp. 236 - 240
• Main Authors: Bydlowski, Sergio Paulo, Pares, Madalena M.N.S., Soares, Rosângela P.S., Lopes, Antonio Augusto B.
• Format: Journal Article
• Language: English
• Published: Northbrook, IL Elsevier Inc 01.07.1998; American College of Chest Physicians
• Subjects: Anticoagulants - metabolism; Atherosclerosis; Becaplermin; Biological and medical sciences; Blood Coagulation - drug effects; Blood platelets; Cell culture; Cell Division - drug effects; Cell growth; Cell Movement - drug effects; cell proliferation; Cells, Cultured; Coagulants - administration & dosage; Coagulants - pharmacology; Diseases of the cardiovascular system; DNA - biosynthesis; DNA synthesis; Dose-Response Relationship, Drug; Growth factors; Humans; Inositol Phosphates - biosynthesis; inositol-phosphate; Kinases; Medical sciences; Mitogens - administration & dosage; Mitogens - pharmacology; Muscle, Smooth, Vascular - drug effects; PDGF receptor; Phosphates; platelet-derived growth factor (PDGF); Platelet-Derived Growth Factor - biosynthesis; Platelet-Derived Growth Factor - metabolism; Protein Binding; Proteins; Proto-Oncogene Proteins c-sis; Radiopharmaceuticals; Radiotherapy. Instrumental treatment. Physiotherapy. Reeducation. Rehabilitation, orthophony, crenotherapy. Diet therapy and various other treatments (general aspects); Receptors, Platelet-Derived Growth Factor - drug effects; Receptors, Platelet-Derived Growth Factor - metabolism; Renal Artery - cytology; Smooth muscle; Stimulation, Chemical; Thrombin - administration & dosage; Thrombin - pharmacology; Thymidine - metabolism; Tritium; vascular smooth muscle cell; Veins & arteries; Sweden; PDGF receptor; DNA synthesis; inositol-phosphate; vascular smooth muscle cell; cell proliferation; platelet-derived growth factor (PDGF); Human; Postoperative; Cell culture; Pathophysiology; Instrumentation therapy; Cardiovascular disease; Exploration; Smooth muscle; Stimulation; Proliferation; In vitro; Myocyte; Arterial disease; Thrombin(drug); Atherosclerosis; Complication; Vascular wall; Platelet derived growth factor
• ISSN: 0012-3692; 1931-3543
• DOI: 10.1378/chest.114.1.236

Thrombin generated at sites of vascular injury not only participates in the coagulation cascade but can also signal other events related to cell mitogenesis and migration. In this report, we investigated the effects of thrombin on the proliferation ofhuman arterial smooth muscle cells (SMCs) in culture and its interaction with platelet-derived growth factor (PDGF). Human arterial SMCs originated from a renal artery were grown in cell culture. The effect of thrombin on DNA synthesis was evaluated by 3H-thymidine incorporation. The effect of thrombin on inositol-phosphate formation by SMCs was also analyzed as well as the binding of PDGF AA and BB to these cells. PDGF secretion was analyzed by radioimmunoassay (RIA). Exposure of cultured human SMCs to thrombin caused an increased rate of DNA synthesis in a dose-response manner, with a maximal stimulatory effect at a concentration of 2.0 U/mL. Thrombin was found to increase the accumulation of inositol phosphates and to increase the production of PDGF as measured by RIA. Exposure of cells to 2.0 U/mL thrombin resulted in a strong decrease in PDGF AA binding to PDGF receptors and did not change PDGF BB binding, probably indicating that PDGF α-receptors could be occupied by endogenously produced PDGF A. Thrombin stimulates human vascular SMC proliferation in a dose-response way, in part by the formation of inositol phosphates. The mechanism responsible for this effect involves, at least in part, an increased endogenous synthesis of PDGF.