I. Ya. Krynytska, M. I. Marushchak

I. Horbachevsky Ternopil State Medical University, Ternopil, Ukraine;
e-mail: marushchak@tdmu.edu.ua

Hepatopulmonary syndrome (HPS) is a pulmonary complication of liver disease characterized by arterial hypoxemia. Altered nitrogen (II) oxide (NO) production has also been implicated in the pathogenesis of the HPS. The present study was designed to evaluate the indices of NO system in the blood serum and lung tissue of animals with different models of hepatopulmonary syndrome. The total NOS activity was performed by monitoring the rate of conversion of L-arginine into citrulline. The total contents of NO metabolites was assessed by evaluation of their amount, which included nitrite ions that were previously presented in the sample (NO₂^–) and also nitrate ions reducted to nitrites (NO₃^–). We found a significant increase in total NOS activity in the lung tissue of Rats of both experimental groups  as compared to control animals, but it was greater in the rats on the 28^th day after the common bile duct ligation. The total concentration of NO₂^– + NO₃^– in the lung tissue of the rats in the experimental group N 1 also significantly increased (5.8 times) and in the rats of the experimental group with carbon – 4.5 times (P < 0.001) vs the control group. Thus, in rats with different models of hepatopulmonary syndrome the activation of nitroxydergic process by a significant increase in nitrogen (II) oxide metabolites contents and total NO synthases activity has been established. Herewith a more pronounced intensification of nitroxydergic processes was observed in rats on the 28th day after the common bile duct ligation.