Content area
Full text
196
Bulletin of Experimental Biology and Medicine, Vol. 147, No. 2, 2009 BIOPHYSICS AND BIOCHEMISTRY
Effects of Histochrom and Emoxypin on Biophysical Properties of Electroexitable Cells
N. P. Mischenko, S. A. Fedoreev, T. A. Zapara*, and A. S. Ratushnyak*
Translated from Byulleten Eksperimentalnoi Biologii i Meditsiny, Vol. 147, No. 2, pp. 155-159, February, 2009 Original article submitted July 24, 2008
Comparative investigation of effects of antioxidant agents histochrom and emoxypin on biophysical characteristics of isolated neurons from shell Lymnaea stagnalis under normal conditions and during oxidative stress was performed. Differently directed effects of these compounds on resting potential and transmembrane ion currents of neural cells under normal conditions were detected. Histochrom provides hyperpolarizing and emoxypin depolarizing effect on neuronal membrane potential. Under conditions of oxidative stress both products possess antioxidant action. Obtained data allows coming closer to understanding of cellular-molecular mechanisms of protective action of compounds.
Key words: histochrom, emoxypin, membrane potential, ion currents, isolated neurons from shell Lymnaea stagnalis
The antioxidant agent histochrom, medicinal formulation of natural echinochrom A (2,3,5,6,8-pentahydroxy-7-ethyl-1,4-naphthoquinone), is used in ophthalmology for treatment of intraocular hemorrhages, diabetic retinopathy, dystrophy, thrombosis of central vein of retina, posttraumatic hemorrhages and for treatment of ischemic heart diseases [6].Histochrom antioxidant action was found to appear by stopping of Fe2+-ascorbate-induced oxidation of liposomes from egg phosphatidylcholine. In this model, histochrom ability to bound potent initiators of lipid peroxidation, Fe2+-ions, into inactive complexes plays a crucial role in inhibition of radical reactions. Antioxidant activity was demonstrated to be provided by b-hydroxyl substituting groups in 2, 3 and 7 position of histochrom molecule [5].However, administration of this compound had no
result in complete understanding of cellular-molecular mechanisms of its action. In comparison with emoxypin (artificial 2-ethyl-6-methyl-3-hydro-xypiridine), compound identical in medical indications, the number of histochrom advantages were revealed, and they can not be explained only with antioxidant properties [1,4]. The subject of this study is a comparison of effects of these medications on simple biological subjects isolated cells.
MATERIALS AND METHODS
Experiments were carried out on isolated neurons from shell Lymnaea stagnalis (age 0.5-1.5 years). Neurons were isolated with mechanical defragmentation following the enzyme treatment of peripharyngeal ganglia. Before electrophysiological investigation, isolated neurons were cultivated on glass supporting plate for 18-20 hours at 6-10oC. Employed physiological solution...