[Intracellular distribution of phosphoorganic cholinesterase inhibitors in rat brain]

Content of organophosphorous inhibitors (with the structure RO/CH3/P/O/SC2H4SC2H5) of cholinesterase as well as their hydrophobic properties (distribution coefficient in hexan/water system) were studied in subcellular fractions of rat brain. Relative content of organophosphorous inhibitors was distinctly decreased in supermicrosomal fraction with increase of hydrophobic properties of the fraction. Nuclear and mitochondrial fractions contained the more hydrophobic substances in relatively higher amount. When homogenate of supermicrosomal fraction was incubated at 37 degrees, own brain cholinesterase was not depressed by organophosphorous inhibitors, containing in the fraction at low concentration. The phenomenon exhibits that content of free organophosphorous inhibitors is distinctly lower in the subcellular fractions studied than amount of the inhibitors, extracted with chloroform.