ABSTRACT
By the method of EPR spectroscopy we studied the intensity of nitric oxide (NO) production after modeling of hypokinesia in rats (limitation of moving activity) through analyses of the amount of NO-containing paramagnetic complexes in tissues of heart and liver. Experimental animals were kept during 60 day protracted hypokinesia. NO amount was assessed by the intensity of EPR spectra of complex (DEDTC)2-Fe(2+)-NO. It was established that after 60 day hypokinesia the 2-3 fold increase of NO quantity occured in heart and liver tissues. The application of a nonspecific inhibitor of NO-synthases, L-NAME, in suspended rats led to a decreased NO quantity up to the value more lower than in control. The obtained results show that the main contribution to the increase in the intensity of NO production during hypokinesia belongs to the fermentative pathway of NO production and the formation of NO by nitrite-reductase activity is not enhanced during hypokinesia.
Subject(s)
Electron Spin Resonance Spectroscopy , Myocardium/metabolism , Nitric Oxide/biosynthesis , Animals , Hypokinesia/metabolism , Hypokinesia/physiopathology , Liver/metabolism , Metabolic Networks and Pathways/drug effects , NG-Nitroarginine Methyl Ester/administration & dosage , Nitric Oxide/metabolism , Nitric Oxide Synthase Type II/antagonists & inhibitors , Nitric Oxide Synthase Type II/metabolism , RatsABSTRACT
Nitric oxide production in heart tissues of rats of different age in the norm and after pharmacological sympathectomy was studied by electron spin resonance spin-trapping. Rats at the age of 14, 21, 70, and 100 days were used in the experiment. The concentration of nitric oxide produced in rat heart tissues proved to considerably decrease during ontogeny. Pharmacological sympathectomy notably decreased nitric oxide production in the heart in 14- and 21-day-old rats: the nitric oxide concentration in the spin trap as well as the level of R and T conformers of hemoglobin nitrosyl complexes decreased. In 70-day-old rats, pharmacological sympathectomy had no notable effect on the level of nitric oxide-containing paramagnetic complexes.
