This chapter focuses on a radioreceptor assay for platelet-derived growth factor (PDGF). PDGF is a polypeptide released during platelet aggregation and formation of thrombus in response to tissue injury. In vitro PDGF is strongly mitogenic to smooth tousle cells, skin fibroblasts, 3T3 cells, and glial cells. The growth promoting properties of PDGF play an important role in tissue repair mechanisms in vivo. Under normal circumstances, the circulating levels of PDGF are very low. Measurable quantities of PDGF are found only when blood is allowed to clot, suggesting that PDGF in blood appears only for a brief period and most probably remains localized to the area of injury. Other growth factors such as insulin, epidermal growth factor (EGF), fibroblast growth factor (FGF), and insulin-like growth factor (IGF) occurring in serum or biological sources also stimulate DNA synthesis in fibroblasts.
ASJC Scopus subject areas
- Molecular Biology