title: The close participation of ET-1 and NO in human hepatic hemodynamics.
abstract: BACKGROUND
  Nitric oxide and endothelin-1 (ET-1) are believed to closely participate in the hepatic circulation. However, there are no clinical studies evaluating the participation of these two molecules in the hepatic circulation.
  
  
  METHODS
  All 27 patients had liver tumors; 6 liver tumors were associated with liver cirrhosis and 12 patients had chronic hepatitis. Portal vein and hepatic arterial blood flow was measured with an electromagnetic flowmeter. Blood was sampled to quantitate endothelin-1 and nitrate/nitrite (NO(x)) from portal veins, peripheral veins and peripheral arteries.
  
  
  RESULTS
  Serum ET-1 levels tended to be higher in patients with liver cirrhosis than patients with chronic hepatitis or patients with normal livers. There were no apparent differences in NO(x) concentrations among underlying liver disease states. Portal blood flow and estimated total hepatic blood flow was adversely correlated with ET-1 in portal veins with relatively higher correlation coefficients whereas arterial blood flow was not correlated to ET-1. On the other hand, arterial plasma ET-1 concentrations were not correlated to any type of blood flow. NO(x) concentrations were not correlated with any type of hepatic blood flow. The ratio of NO(x) to ET-1 in portal veins was correlated with portal blood flow and estimated hepatic blood flow. This correlation coefficients were higher than correlation coefficients between ET-1 concentrations in portal veins, and portal and hepatic blood flow.
  
  
  CONCLUSIONS
  ET-1 levels in portal blood are significantly associated with portal blood flow and total hepatic blood flow in humans, and ratio of NO(x) to ET-1 is better indicators than either ET-1 or NO(x) alone. Although this study has limitations because it was carried out in a clinical setting, the data may contribute to the understanding of human hepatic hemodynamics.
authors.affiliation: Department of Hepatobiliarypancreatic Surgery, Tokyo Medical and Dental University, 1-5-45 Yushima Bunnkyo ku, Tokyo 113-8519, Japan.
authors.forename: Norio
authors.initials: N
authors.lastname: Noguchi
authors.forename: Kenichi
authors.initials: K
authors.lastname: Teramoto
authors.forename: Takanori
authors.initials: T
authors.lastname: Ochiai
authors.forename: Takumi
authors.initials: T
authors.lastname: Irie
authors.forename: Atushi
authors.initials: A
authors.lastname: Kudou
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Kurokawa
authors.forename: Noriaki
authors.initials: N
authors.lastname: Nakamura
authors.forename: Shinnji
authors.initials: S
authors.lastname: Tanaka
authors.forename: Tohru
authors.initials: T
authors.lastname: Kawamura
authors.forename: Shigeki
authors.initials: S
authors.lastname: Arii