Digestive Diseases and Sciences

, Volume 40, Issue 9, pp 1941–1945 | Cite as

Hemodynamic effects of hypothyroidism induced by methimazole in normal and portal hypertensive rats

  • Ran Oren
  • Nir Hilzenrat
  • Yoram Maaravi
  • Arie Yaari
  • Emanuel Sikuler
Liver: Cirrhosis, Fibrosis, Portal Hypertension, and Transplantation

Abstract

Portal hypertension is accompanied by a hyperdynamic circulatory state that shares some similarities with thyrotoxicosis. This study was conducted in order to investigate the hemodynamic effects of hypothyroidism in a rat model with portal hypertension induced by partial portal vein ligation (PVL). Four groups of 10 rats each were studied: normal control and hypothyroid rats, and PVL control and hypothyroid rats. Hypothyroidism was induced by methimazole 0.04% in drinking water. Hemodynamic measurements were performed using the radioactive microsphere technique. Induction of hypothyroidism was confirmed by elevated TSH levels. In the PVL groups, hypothyroidism ameliorated the hyperdynamic circulation. Portal venous inflow and portal pressure dropped significantly: 7.1±0.2 vs 4.8±0.3 ml/min/100 g body wt (P<0.01) and 13.4±0.9 vs 10.9±0.8 mm Hg; (P<0.01), respectively. In normal rats, hypothyroidism was manifested by a hypodynamic circulatory state. These results demonstrate that hypothyroidism induced by methimazole is followed by amelioration of the hyperdynamic circulation, normalization of portal venous inflow, and reduction of portal pressure.

Key Words

portal hypertension hypothyroidism hemodynamics methimazole portal vein ligation 

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Copyright information

© Plenum Publishing Corporation 1995

Authors and Affiliations

  • Ran Oren
    • 1
    • 2
  • Nir Hilzenrat
    • 1
    • 2
  • Yoram Maaravi
    • 1
    • 2
  • Arie Yaari
    • 1
    • 2
  • Emanuel Sikuler
    • 1
    • 2
  1. 1.Department of MedicineHadassah University HospitalJerusalem
  2. 2.Hepatic Hemodynamic Laboratory, Department of Medicine, Soroka Medical Center and Faculty of Health SciencesBen-Gurion University of the NegevBeer-ShevaIsrael

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