Sıçanlarda %70 Hepatektomi Sonrası Oluşan Yerel ve Sistemik Anjiyojenik ve Antianjiyojenik Yanıt

Abstract

. Aim: Angiogenesis is an important component of liver regeneration and occurs as a result of interaction between the proangiogenic and anti-angiogenic activities. This study investigated these two activities at both local and systemic levels and studied the possible correlation between them during hepatic regeneration. Material and method: In this study 64 female rats underwent 70% hepatectomy and were sacrificed on the posthepatectomy days 1, 3, 5, 7, 10, 14 and 21. In each group local and systemic effects of angiogenesis and anti-angiogenesis were evaluated. Angiogenesis was defined by immunoreactivity to VEGFR-2, while anti-angiogenesis was determined by immunoreactivity to endostatin. Systemic VEGF and endostatin were identified by ELISA with corresponding antibodies. Results: Both VEGF and VEGFR-2 began to rise on day 3. On day 5 both of them reached local peak with 260,60 pg/ml for VEGF and 3.63 degrees for VEGFR-2 expression. At day 21 both parameters returned to basal level. Peak values of systemic endostatin (68,83 ng/ml) were detected on day 7. Local endostatin expression in tissue was found to be high through groups from 7th to 14th days (with mean degree of expression equalling 2). On day 14 through 21 when tissue endostatin went decreasing systemic one made some plateau. Discussion: As one of the aims of this study, the ratio or correlation between systemic VEGF and endostatin proved to have high level correlation coefficients (with ? > 0.69) among 5th, 7th, 10th, 14th and 21st day groups. Obtained VEGF-endostatin ratio is thought to be able to supply us with an instrument to measure angiogenesis and anti-angiogenesis balance which is to be defined by prospective clinical studies in the future. Keywords: vascular endothelial growth factor, endostatin, VEGF-endostatin ratio, angiogenesis, anti-angiogenesis, liver regeneration. Supported by: HUSM, Scientific Research Unit, 012 D06 101 013.