DISFUNCŢIA ENDOTELIALĂ. SURSA MODIFICĂRILOR PATOGENICE ŞI A PROGRESIEI CLINICE ÎN HIPERTENSIUNEA PORTALĂ.

Portal hypertension (PHT) is responsible for the more severe and even lethal complications of chronic liver disease and cirrhosis. Among structural and functional changes of the liver in portal hypertension, recent pathogenic approaches show an initial involvement of the hepatic vascular structures. Endothelial dysfunction results in impaired vascular tone, increased intrahepatic vascular resistance and development of hyperdinamic circulation. Nitric oxide, endothelin, endothelial-derived contracting factors are powerful vasoactive substances released from the endothelium in response to both humoral and mechanical stimuli that can profoundly affect both the function and structure of the underlying vascular smooth muscle. Pharmacotherapy for PHT is aimed at decreasing both intrahepatic vascular resistance (increase bioavailability of vasoactive substances) and reducing elevated splanchnic blood flow. [ABSTRACT FROM AUTHOR]