Stimulation of granulation tissue formation by platelet-derived growth factor in normal and diabetic rats.

Abstract

Subcutaneous implantation of Hunt-Schilling wound chambers in rats induces a wound repair response causing the chamber first to fill with fluid and subsequently with connective tissue. The presence of a type I collagen gel encouraged a more rapid dispersion of cells throughout the chamber but had no effect on the rate of new collagen deposition. Addition of platelet-derived growth factor (PDGF; 50 ng/chamber) to the collagen-filled chambers caused an earlier influx of connective tissue cells, a marked increase in DNA synthesis, and a greater collagen deposition in the chamber during the first 2 wk after implantation. After 3 wk, however, the levels of collagen were similar in PDGFsupplemented and control chambers. Diabetic animals exhibited a decreased rate of repair which was restored to normal by addition of PDGF to the wound chamber. Combinations of PDGF and insulin caused an even more rapid increase in collagen deposition. These results suggest that the levels of various growth factors, particularly PDGF, may be limiting at wound sites and that supplementation of wounds with these factors can accelerate the rate of new tissue formation.

Regulation of connective tissue growth factor gene expression in human skin fibroblasts and during wound repair.

“…These data demonstrate that CTGF mRNA induction by TGF-f does not require de novo protein synthesis, indicating that the increase in CTGF mRNA is directly regulated by TGF-fl. tissue infiltration, neovascularization, and matrix deposition (Schilling et al, 1959;Hunt et al, 1967;and Grotendorst et al, 1985). (Figure 8).…”

“…The TGF-f1 transcript was present at the earliest times assayed with it highest level on day 3 followed by a rapid decrease to very low levels by day 9. Histological analysis of day 3 tissue reveals large numbers of leukocytes (Grotendorst et al, 1985) that produce TGF-fl (Assoian et al, 1987;. Interestingly, the CTGF transcript exhibits a very different pattern of expression with a peak on day 9 that coincides with the initial ingrowth of granulation tissue composed of connective tissue cells and vascular endothelial cells both of which express the CTGF mRNA in culture (Bradham et al, 1981).…”

“…The myc probe was a 1. (Grotendorst et al, 1985). Six chambers were implanted in each animal in a total of 30 animals.…”

A novel primate model of delayed wound healing in diabetes: dysregulation of connective tissue growth factor

“…The most common collection device has been the sponge [13,14,16], where cells invade and lay down collagen. Other studies have involved insertion of porous cylinders, most commonly the HuntSchilling stainless steel mesh cylinder [17]. These cylinders have been useful for the study of wound repair as they induce a response that exhibits the classic phases of inflammation, connective tissue infiltration, neovascularisation and matrix deposition [15,18].…”

Platelet-Derived Growth Factor B-Chain of Hematopoietic Origin Is Not Necessary for Granulation Tissue Formation and Its Absence Enhances Vascularization

“…[11][12][13] Many reports have also demonstrated that exogenous PDGF can enhance angiogenesis. In mice, implantation of PDGF B-chain-transfected melanoma cells resulted in increased fibrovascular stroma development relative to untransfected cells.…”