ABSTRACT
Objective To investigate the effect of soluble Tie2 fusion protein(sTie2/Fc)on the angiogenesis of peritoneal vessels in uremic peritoneal dialysis (PD) rats.Methods Rats were randomly divided into 6 groups:normal rats as control group (group1),rats with sham operation (group2),uremic rats without PD (group3),uremic rats dialyzed with 4:25％ PD solution (group4),uremic rats dialyzed with 4.25％ PD solution and treated by subcutaneous injection of 2.5 μg/kg sTie2/Fc (group5),uremic rats dialyzed with 4.25％ PD solution and treated by subcutaneous injection of 5.0 μg/kg sTie2/Fc (group6).sTie2/Fc was given every other day during peritoneal dialysis period,total 14 doses.After regular PD for 28 days,RT-PCR and tissue immunohistochemical staining were used to detect the mRNA and protein expressions of Angpt-2 in peritoneal tissues in each group of rats.Microvessel density (MVD) of peritoneum was detected and quantified with immunohistochemical staining by using anti-CD34 antibody.Results The expression of Angpt-2 mRNA and protein was found in each group.There was no significant difference of.Angpt-2 expression both in mRNA and protein level between group1 and group2.Compared with group1,the mRNA and protein expression of Angpt-2 were significantly increased in group3 and group4 (all P＜0.05).Compared with group3,the mRNA and protein expression of Angpt-2 were significantly increased in group4 (all P＜0.05).Compared with group 4,the mRNA and protein expression of Angpt-2 were significantly decreased in group5 and group6 (all P＜0.05).Compared with group5,the mRNA and protein expression of Angpt-2 were significantly decreased in group6 (all P＜0.05).Only few new microvessel was found in group1 and group2.Compared with group1,MVD was significantly up-regulated in group3 and group4 (all P＜0.05).Compared with group4,MVD was significantly down-regulated in group5 and group6 (all P＜0.05).Conclusions Peritoneum neoangiogensis can be effectively inhibited by sTie2/Fc in uremic rat treated with PD.Blocking of signal transduction may be involved in the mechanism of sTie2/Fc inhibiting peritoneal angiogenesis.