Effect of the nitric oxide synthesis inhibitor L-NAME on the isolated rat heart after hypokinesia

Abstract

The effects of a non-selective nitric oxide synthase inhibitor L-NAME on the functional parameters of the isolated rat heart after a 30-day period of hypokinesia were studied. Electron paramagnetic resonance spectroscopy was employed in the analysis of a role for L-NAME in the intensity of nitric oxide production in rat heart tissues. The intensity of nitric oxide synthesis was assessed by the intensity of the signal belonging to the (DETC)2-Fe2+-NO complex. It was found that L-NAME decreased nitric oxide production on average by 69%. The Langendorff isolated perfused heart was used to evaluate cardiac activity, and the following parameters were measured: pressure generated by the left ventricle, heart rate, and coronary flow. Addition of the nitric oxide synthesis inhibitor L-NAME induced an increase in inotropic function and normalization of heart rate.