[Effect of cyclic nucleotides on the sensitivity of early sea urchin embryos to cytotoxic neuropharmacological preparations].

It has been shown that cytotoxic action of neuropharmacological drugs (transmitter antagonists) on early urchin embryos is reduced or abolished by cyclic nucleotides and sodium fluoride. Such a protective action differs in cAMP and dibutyryl analogs of cyclic nucleotides, depending on the chemical structure of an embryotoxic substance. It is suggested that, endogenous intracellular "prenervous" transmitters and cyclic nucleotides are interrelated in the regulation of cell division in urchin embryos.