Functional nitric oxide conjugate systems state/restored heart thiols of rats in modeling isadrine-pituitrin’s myocardial infarction using metabolite-tropic cardioprotector “Angiolin”

Background: According to modern researches, endothelial dysfunction (ED) is one of the primary pathogenetic elements of cardiovascular diseases (myocardial infarction [MI], ischemic heart diseases, cerebral ischemic stroke, atherosclerosis, arterial hypertension, pulmonary hypertension, heart failure, and dilated cardiomyopathy) as well as obesity, hyperlipidemia, diabetes and hyperhomocysteinemia. The aim of this work was to study the influence of potential metabolitotropic cardioprotector “Angiolin” on the parameters of conjugate systems nitric oxide (NO)/restored thiols in heart under isadrine-pituitrin MI.Methods: This study was performed on Wistar white rats weighing 190-210 g. Biochemical, immune-enzyme analysis and histoimmunechemical study were performed.Results: In histological sections of hearts of the rats receiving Angiolin in parenteral dosing 50 mg/kg 30 mins before each pituitrin injection the density of endothelial NO-synthase (NOS)-positive cells increased by 29% and the density of inducible NOS-positive cells decreased by 23.3%. In cytosolic fraction of myocardium homogenate NOS activity increased by 27%, the concentration of NO stable metabolites increased by 70% and the content of nitrosative stress marker nitrotyrosine decreased by 42% when compared with control group. At the same time in similar samples of heart homogenate the increase of restored thiol groups’ level by 53.3%, methionine - by 35.1%, cysteine - by 170% and activity of glutathione reductase - by 186% was noted. The administration of reference drug mildronate to the animals with MI in dose 100 mg/kg did not result in significant changes of the studied parameters of thiol-disulfide system and NO system of the heart when compared with control group.Conclusions: Angiolin does not influence directly on NOS in MI, but at the same time protects NO from nitrosative stress increasing restored equivalents of thiol-disulfide system

Sorption of polar organic solvents and water by graphite oxide : thermodynamic approach

Sorption of polar organic solvents CH3OH, C4H8O (THF), CH3CN, C3H7NO (DMF), C2H6OS (DMSO), C5H9NO (NMP) and water was quantitatively evaluated for Hummers (H-GO) and Brodie (B-GO) graphite oxides at T = 298K and at melting temperature (Tm) of the solvents. H-GO showed stronger sorption compared to B-GO for all studied solvents and the increase of sorption upon lowering temperature was observed for both H-GO and B-GO. Thermodynamic equations allowed to explain earlier reported "maximums" of swelling/sorption in the binary systems H-GO – solvent at Tm. The specific relation between the values of enthalpies of sorption and melting leads to the change of sign in enthalpies of sorption at Tm and causes maximal swelling/sorption. The same thermodynamic explanation was given for the "maximum" on the swelling vs. pressure dependence in B-GO and H-GO – H2O systems earlier reported at pressure of phase transition "liquid water-ice VI". Notably higher sorption of H2O was observed for H-GO compared to H-GO membrane (H-GOm) at high relative humidity (RH), RH > 0.75. Experimental sorption isotherm of H-GOm was used to simulate permeation rates of water through H-GOm and to estimate effective diffusion coefficient of water through the membrane