Formation of Mutagens by Heating the Aqueous Solution of Amino Acids and Some Nitrogenous Compounds with Addition of Glucose

A ³H-labeled bicyclic phosphate (BP), 4-[2,3-³H]propyl-2,6,7-trioxa-1-phosphabicyclo-[2.2.2]octane 1-oxide, bound specifically to rat brain synaptic membrane preparations. The apparent dissociation constant and the quantity of the BP bound at saturation were estimated to be about 30 μm and about 2 pmol per mg of protein, respectively. BP analogs except 4-amino BP, which is extremely low in toxicity, inhibited the binding but no obvious correlation was observed between the toxicity and the inhibitory potency of the BP analogs. The binding was also inhibited by high concentrations of GABA and picrotoxinin, whereas it was enhanced by bicuculline methiodide.