The actions of two groups of bioregulators, which have opposite effect to adenylate cyclase and phosphoinositide cellular signaling systems, on enzymatic hydrolysis of the synthetic distearoylphosphatidylcholine of Langmuir monolayer films by phospholipase A2, were studied. It was found, that bioregulators, which activate adenylate cyclase and(or) inhibit phosphoinositide signaling systems of the cell, in the 10-4 M concentration, significantly reduce enzymatic cleavage of phospholipids (most strongly - isoprenaline, yohimbine, nifedipine). For physiologically active substances, which inhibit adenylate cyclase and(or) activate phosphoinositide signaling systems, of authentic influence on current of fermentative reaction is not revealed. [ABSTRACT FROM AUTHOR]