Gastroenterology

Gastroenterology

Volume 118, Issue 5, May 2000, Pages 937-944
Gastroenterology

Liver, Pancreas, and Biliary Tract
Contribution of nitric oxide to the pathogenesis of cirrhotic cardiomyopathy in bile duct–ligated rats,☆☆,

https://doi.org/10.1016/S0016-5085(00)70180-6Get rights and content

Abstract

Background & Aims: Decreased cardiac contractility and β-adrenergic responsiveness have been observed in cirrhosis, but the etiology remains unclear. We aimed to test the role of nitric oxide (NO), a negative inotropic agent, in the pathogenesis of cirrhotic cardiomyopathy in a rat model. Methods: Cirrhosis was induced by bile duct ligation. Four weeks after ligation or sham operation, cardiac levels of tumor necrosis factor (TNF)-α, guanosine 3,5'-cyclic monophosphate (cGMP), inducible NOS (NOS2), and endothelial constitutive NOS (NOS3) messenger RNA (mRNA) and protein were determined. Serum nitrite/nitrate level was measured. Cardiac contractile function was evaluated in isolated left ventricular papillary muscles in the absence and presence of the NOS inhibitor nitro-L-arginine methyl ester (L-NAME). Results: Cardiac TNF-α, NOS2 mRNA and protein, cGMP, and serum interleukin (IL)-1β and nitrite/nitrate levels were significantly higher in cirrhotic rats than sham controls. No significant differences in NOS3 mRNA or protein were found between cirrhotic and sham control rats. Baseline isoproterenol-stimulated papillary muscle contractile force was significantly lower in the cirrhotic group; with L-NAME incubation, contractile force increased significantly in cirrhotic rats but was unaffected in the controls. In normal papillary muscles, IL-1β attenuated the contractility, but coincubation with L-NAME again reversed this attenuation. Incubation with the exogenous NO donor S-nitroso-N-acetyl-penicillamine also blunted papillary muscle contractility. Conclusions: These results suggest that cytokine-induced stimulation of NOS2 plays a significant role in the pathogenesis of cirrhotic cardiomyopathy.

GASTROENTEROLOGY 2000;118:937-944

Section snippets

Reagents and enzymes

DNA synthase, RNA superscript synthase, and polymerase chain reaction (PCR) buffer were purchased from GIBCO BRL, Life Technologies (Gaithersburg, MD). Agarose was obtained from ICN Biomedicals (Aurora, OH), sodium nitrite from BDH (Toronto, ON), and L-NAME and its inactive enantiomer nitro-D-arginine-methyl ester (D-NAME) from Bachem (Torrance, CA). Other reagents were purchased from Sigma Chemical Co. (St. Louis, MO), Bio-Rad (Hercules, CA), or Fisher Scientific (Fairlawn, NJ) and were the

Cytokine levels

TNF-α levels in cardiac homogenates showed a significant increase in the BDL cirrhotic rats compared with those of sham-operated controls (Table 2). Serum IL-1β level was increased in BDL cirrhotic rats compared with that in sham-operated controls (Table 2).

Ventricular NOS2 and NOS3 mRNA and protein expression

A representative NOS2 mRNA RT-PCR Polaroid is shown in Figure 1.

. RT-PCR of NOS2 transcription from rat hearts. Lane 1, 1-kilobase (kb) ladder; lanes 2 and 3, control; lanes 4 and 5, BDL; lane 6, lipopolysaccharide (LPS)-treated positive

Discussion

In the past few years, some evidence has suggested that NO production is increased in the vasculature in cirrhosis5, 6 (and see Bomzon and Blendis27 for review). However, whether this is predominantly caused by NOS2 stimulated by cytokinemia or NOS3 secondary to the hyperdynamic circulation and shear stress remains unclear. Our data using the nonspecific NOS2 and NOS3 inhibitor L-NAME in the isolated papillary muscle strongly support the results of Van Obbergh et al.16 who found that treatment

References (40)

  • S Kanwar et al.

    Nitric oxide synthase activity in portal-hypertensive and cirrhotic rats

    J Hepatol

    (1996)
  • AJ De Belder et al.

    Nitric oxide synthase activities in human myocardium

    Lancet

    (1993)
  • D Stoyanovsky et al.

    Nitric oxide activates skeletal and cardiac r yanodine receptors

    Cell Calcium

    (1997)
  • G Garcia-Tsao et al.

    Bacterial translocation to mesenteric lymph nodes is increased in cirrhotic rats with ascites

    Gastroenterology

    (1995)
  • J Napoli et al.

    Increased intrahepatic messenger RNA expression of interleukins 2, 6 and 8 in human cirrhosis

    Gastroenterology

    (1994)
  • K Sugishita et al.

    Cellular basis for the acute inhibitory effects of IL-6 and TNF-alpha on excitation-contraction coupling

    J Mol Cell Cardiol

    (1999)
  • B Stein et al.

    Endotoxin and cytokines induce direct cardiodepressive effects in mammalian cardiomyocytes via induction of nitric oxide synthase

    J Mol Cell Cardiol

    (1996)
  • S. Sherlock

    Vasodilatation associated with hepatocellular disease: relation to functional organ failure

    Gut

    (1990)
  • C Guarner et al.

    Increased serum nitrite and nitrate levels in patients with cirrhosis: relationship to endotoxemia

    Hepatology

    (1993)
  • MP Pizcueta et al.

    Effects of inhibiting nitric oxide biosynthesis on the systemic and splanchnic circulation of rats with portal hypertension

    Br J Pharmacol

    (1992)
  • Cited by (134)

    • Cirrhotic cardiomyopathy

      2022, Cardio-Hepatology: Connections Between Hepatic and Cardiovascular Disease
    • Diagnosis and Management of Cirrhotic Cardiomyopathy

      2022, Journal of Clinical and Experimental Hepatology
    View all citing articles on Scopus

    Address requests for reprints to: Samuel S. Lee, M.D., 3330 Hospital Drive N.W., Calgary, Alberta, T2N 4N1, Canada. e-mail: [email protected]; fax: (403) 270-0995.

    ☆☆

    Supported by a research operating grant from the Medical Research Council of Canada. Dr. Lee is a Scholar of the Alberta Heritage Foundation for Medical Research.

    Drs. Liu and Ma contributed equally to this work.

    View full text