AN INVESTIGATION OF THE POSSIBLE ROLE OF PHOSPHOINOSITIDES AS REGULATORS OF ACTION POTENTIALS BY STUDYING THE EFFECT OF ELECTRICAL STIMULATION, TETRODOTOXIN AND CINCHOCAINE ON PHOSPHOINOSITIDE LABELLING BY ³²P IN RABBIT VAGUS

Abstract

Abstract— The effect of electrical stimulation, tetrodotoxin and cinchocaine (the latter two substances abolish action potentials) on the incorporation of [ 32 P]orthophosphate into the phosphoinositides of isolated rabbit vagus nerve has been studied. Electrical stimulation, or treatment with tetrodotoxin, had little significant effect on the incorporation of [ 32 P]orthophosphate into the phosphoinositides. Cinchocaine, however, caused a 3.5–4.4‐fold increase ( P = < 0.001) in monophosphoinositide labelling. These findings are discussed in view of the possible function of the phosphoinositides in the nervous system.