RESUMO
OBJECTIVE: To evaluate the growth factor responses associated with myocardial angiogenesis. DESIGN: Mice were treated with transmyocardial revascularization (TMR) and evaluated for angiogenic and growth factor responses. METHODS: TMR was performed via thoractomy with a 27 g needle. At 2, 5, and 7 days post-treatment, hearts were removed from the TMR treated and control groups, then assayed for angiogenesis, fibroblast growth factor (FGF)-2 expression and vascular endothelial cell growth factor (VEGF) expression. RESULTS: TMR caused an angiogenic reaction in the myocardial blood vessels at 7 days post-TMR treatment. Elevated FGF-2 corresponded with increased TMR related angiogenesis. VEGF levels only increased in hearts that were prewounded then TMR treated. CONCLUSIONS: The data show that TMR stimulates myocardial angiogenesis. The angiogenic reaction is mediated by FGF-2 which increased in most experimental treatment groups. The VEGF response was more specific, requiring prewounding then TMR treatment for a VEGF increase.
Assuntos
Fator 2 de Crescimento de Fibroblastos/metabolismo , Coração/fisiologia , Neovascularização Fisiológica/fisiologia , Cicatrização/fisiologia , Animais , Fatores de Crescimento Endotelial/fisiologia , Imuno-Histoquímica , Linfocinas/fisiologia , Camundongos , Revascularização Miocárdica , Miocárdio/citologia , Miocárdio/metabolismo , Regulação para Cima , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio VascularRESUMO
Although the gene encoding prion protein (PrP) is the major determinant of susceptibility to prion disease, other genes also affect prion incubation time in mice and may be involved in prion replication. Scrapie incubation time was analyzed as a quantitative trait using crosses between SJL/J and CAST/Ei mice; these mouse strains encode identical PrP molecules but have different incubation periods. Our analysis revealed loci on Chromosomes 9 and 11 that affect prion susceptibility.