Stimulation of β-adrenoreceptors with low (10(-8) and 10(-7) M) or high (10(-6) M) doses of isoproterenol in hypokinetic rats treated with L-NAME (a non-selective blocker of NO synthases) decreased or increased myocardial contractility, respectively. In control rats, all examined doses of isoproterenol used under blockade of NO synthases inhibited myocardial contractility.
The electron paramagnetic resonance method was used to study the intensity of nitric oxide production by analyzing the amount of NO-containing paramagnetic complexes in the heart, liver, and spinal cord tissues of 7- and 16-week-old rats growing under restricted mobility conditions. Nitric oxide production was assessed by the intensity of the EPR signal belonging to the (DETC)2-Fe2+NO complex. The results obtained show that growth under conditions of restricted motility leads to an increase in NO production in all organs under study, with the greatest increase observed in 7-week-old rats. Keywords: nitric oxide, heart, liver, spinal cord, electron paramagnetic resonance.
Electron paramagnetic (EPR) spectroscopy study showed that 90-day hypokinesia in rats is accompanied by an increase in NO production in the heart. A nonselective NO synthase inhibitor L-NAME decreased the content of NO in the heart atria and ventricles of hypokinetic rats by 67-70%. A selective inhibitor of inducible NO synthase, aminoguanidine, also decreased the level of NO in the heart atria and ventricles of hypokinetic rats by 60-65%. Our results indicate that the increase in NO production during hypokinesia is associated with activation of NO synthases.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.