Gangliosides and other lipid micelles. A study of amine binding by a dialysis/fluorescence method

The binding of serotonin to bovine adrenal medulla gangliosides (BAMG), bovine brain gangliosides (BBG), and BBG-synthetic lecithin mixed micelles has been demonstrated by a rapid technique using fluorescence monitoring of dialysis rates. BAMG micelles bound 0.10 mM serotonin at about half the efficiency of BBG micelles having the same sialic acid concentration (0.50 mM) in water. In water, the effect of BBG micelles was essentially identical to that of mixed micelles containing the same quantity of BBG. Ca2+ (1.20 mM), however, cancelled the effect of the mixed micelles on serotonin dialysis and reduced the effect of BBG micelles to about one quarter of that observed in water. These and other observations are related to earlier studies and to neurochemical processes which may involve gangliosides.