Adrenomedullin level in cirrhotic rats: relationship with renal functions and some vasoconstrictors

ABSTRACT

Purpose: to assess the role of endothelial factors as adrenomedullin [AM] and nitric oxide [NO] in modulating intrahepatic circulation and the role of NO inhibitors. Also, to investigate their relationship with some renal functions and some vasoconstrictors as norepinephrine [NE] and plasma rennin activity [PRA]. a significant increase of AM levels, plasma and urinary No was observed at both groups of cirrhosis. They significantly declined upon No inhibition. The levels were significantly elevated at cirrhosis with ascites than without ascites. PRA significantly increased in both cirrhotic groups with ascites but insignificantly changed at cirrhotic groups without ascites. NE significantly increased at cirrhotic groups [group II and III]. Both NE and PRA significantly declined upon NG nitro L-argenine methylester [L-NAME] administration. AM levels were negatively correlated to mean arterial pressure [MAP] and glomerular filtration rate [GFR]. While it was positively correlated to NE levels, PRA, plasma and urinary NO metabolites, serum Na+ level and urinary sodium excretion [UnaV]. at cirrhosis, there were significantly increased circulating levels of AM, plasma and urinary NO which could be responsible for the arterial vasodilatation. The mechanism of AM effects could be due to NO release. There were increased levels of NE and PRA due to arterial underfilling which activates a baroreceptor mediated neurohumoral response to counterregulate the vasodilatation. NO inhibition revered haemodynamic changes associated with cirrhosis. This raises the possibility of using long term NO inhibition to correct complications associated with cirrhosis and Bilharzial hepatic fibrosis [BHF]