Effect of the preservative benzalkonium chloride eye drops on the state of mitochondrial enzymes tissues of the anterior eye

Introduction. Despite the proven side effects caused by benzalkonium chloride (BAC), the worldwide most glaucoma patients continue to use eye drops containing this preservative, so the investigation by studying the effect of benzalkonium chlo?ride on the condition of the tissues of the anterior eye is important. Purpose. To study the effect of the preservative benzalkonium chloride eye drops on the state of mitochondrial enzymes tissues of the anterior eye. Material and methods. 34 rabbits were used for the experiment, they were divided into 3groups: group 1 ? control (10 rabbits), group 2 ? investigated (12 rabbits), treated with instillation of 0.02 % solution of BAC, group 3 ? investigated (12 rabbits) which received 0.1 % solution of BAC. The cornea, conjunctiva and tear fluid were studied. The activity of mitochondrial enzymes (malate dehydrogenase, hlutamatdehidrohenazy, succinate dehydrogenase and cytochrome oxidase) was determined in the cornea, conjuctiva and tear fluid. Results. The analysis of the results presented suggest that benzalkonium chloride in low (0.02 % solution) and higher (0.1 % solution) concentration cause expressive disturbance of oxidation of the biological substrates in the mitochondria tissues of the anterior eye. However, a clear dose-dependent effect of BAC was found only in relation to cytochrome oxidase ? an enzyme localized outside the inner mitochon-drial membrane. At the same time, there was found no statistically significant dose dependence of enzymes that are localized at inside of the mitochondrial matrix (malate dehydrogenase, hlutamatdehidrohenazy, succinate dehydrogenase). Conclusions. 1. Preservative eye drops BAC at the concentration of 0.02 and 0.1 % causes severe damage of the mitochondrial oxidative function of tissues of the anterior eye: the cornea, conjunctiva. 2. There was revealed a clear dose-dependentinhibitory effect on the enzyme BAC of the inner mitochondrial membrane ? cyto-chrome oxidase.The enzyme activity in using higher concentrations of BAC in the cornea and conjunctiva decreased by 39.6 and 46.5 %, respectively.