Tetanus toxin: inhibitory action in chromaffin cells is initiated by specified types of gangliosides and promoted in low ionic strength solution.

Adrenal medullary chromaffin cells preloaded with [3H]noradrenaline release the hormone by exocytosis upon stimulation with carbachol. This exocytosis is not influenced by tetanus toxin (Tetx) which can block the release of transmitters from nerve endings. Preincubation of chromaffin cells with gangliosides followed by toxin exposure in low ionic strength solution results in a decrease of stimulated catecholamine release. The inhibition of exocytosis is most evident when cells are pretreated with the ganglioside GD lb. Cells treated with GTlb are 10 times less sensitive, those treated with GDla and GMl even 30 times less sensitive to Tetx. Thus GDlb appears to be the principal carrier for Tetx in chromaffin cells whereas the other gangliosides only play a minor role.