ENHANCED ANGIOGENESIS AND GRANULATION-TISSUE FORMATION BY BASIC FIBROBLAST GROWTH-FACTOR IN HEALING-IMPAIRED ANIMALS

The effect of basic fibroblast growth factor (bFGF) on angiogenesis an d granulation tissue formation in normal and healing-impaired animals was studied. bFGF showed a dose-dependent enhancement of granulation t issue formation in the subcutaneous implantation of a paper disk in no rmal rats. Application of bFGF restored the formation in healing-impai red rat models treated with steroid, chemotherapy and X-ray irradiatio n. The angiogenic activity of bFGF was also demonstrated in the micro- pocket assay using the cornea of rabbits. Repeated applications of bFG F accelerated closure of full-thickness excisional wounds in diabetic mice, but the high doses showed rather diminished response. In contras t histological and gross evaluation of wound tissues revealed enhanced angiogenesis and granulation tissue formation in a dose-dependent man ner. The findings suggested that the topical application of excess amo unts of bFGF might reduce its ability to promote wound closure because of the prolonged responses in both neovascular and granulation tissue formation.