Related Experiment Video
Updated: Aug 29, 2026

Invasive Hemodynamic Characterization of the Portal-hypertensive Syndrome in Cirrhotic Rats
Published on: August 1, 2018
Effects of parasympathetic blockade on hepatic and portal venous flow
Yoshiko Miyanaga1, Toshiyuki Oniki, Hitoshi Kitamura
1Department of Internal Medicine, Kawaguchi-Kogyo General Hospital, Japan.
Background/Aims:
To investigate the effect of parasympathetic blockade on the hepatic circulation, a study was performed in healthy men because the precise knowledge of factors to affect the hepatic circulation is required for the evaluation of liver diseases.
Methodology:
Doppler measurements of the hepatic venous and portal venous flow were obtained with measurements of cardiac function before and after the administration of atropine sulfate, 0.02 mg/kg.
Results:
Parasympathetic blockade increased heart rate and cardiac output and changed diastolic right ventricular filling pattern. However, portal venous flow remained unchanged. Hepatic venous flow was triphasic at rest in 15 of the 20 subjects (75%). The amplitude of the oscillation of hepatic venous flow velocity was significantly reduced in association with an increase in heart rate and the hepatic venous flow pattern was significantly influenced by parasympathetic blockade in accordance with a change in right ventricular filling pattern.
Conclusions:
The autoregulation of portal venous flow was suggested to exist and that the influences of parasympathetic activity and/or heart rate affected hepatic venous flow pattern.
Related Concept Videos
Portal Hypertension
Hepatic Portal System
At its core, the hepatic portal vein is the result of a confluence of the superior and inferior mesenteric veins along with the splenic vein. Each of these veins has a unique role. The superior mesenteric vein is responsible...
Effect of Hepatic Disease on Pharmacokinetics: Drug Dosing and Hepatic Blood Flow
Autoregulation of Blood Flow
Chemical Signaling in Autoregulation
Chemical signaling operates at the precapillary sphincter level, inciting either contraction or relaxation.
Drugs Acting on Autonomic Ganglia: Blockers
Effect of Hepatic Disease on Pharmacokinetics: Pathophysiologic Assessment and Liver Function Test

