EXOGENOUSLY APPLIED GANGLIOSIDES (GM(1), GD(1A) AND G(MIX)) FAIL TO FACILITATE THE INDUCTION OF LONG-TERM POTENTIATION (LTP) IN THE SLICES OF HIPPOCAMPUS AND SUPERIOR COLLICULUS OF THE GUINEA-PIG

To confirm the effect of gangliosides on the facilitation of the induction of long-term potentiation (LTP), slices of hippocampus and superior colliculus from guinea pig were prepared. One group of slices was incubated in the standard medium containing gangliosides (GM(1), GD(1a), or a mixture of gangliosides from bovine brain, each at a concentration of 70 mu M) for 2 h. The other group of slices was incubated in the standard medium only. In both groups of slices, tetanic stimulation induced LTP in a similar manner. In low Ca2+ (1 mM) medium, LTP was not induced in either group of slices. Thus, the present experiments could not confirm previous reports indicating that exogenously applied gangliosides facilitate the induction of LTP.