The Question of Relationship Between Golgi Vesicles and Synaptic Vesicles in Octopus Neurons

Abstract

Electron microscopy of the vertical lobe of octopus brain shows that the synaptic knobs of axons with perikarya in the median superior frontal lobe have synaptic vesicles, approximately 28% of which are dense-cored (or granulated). In contrast, the endings of the amacrine neurons in the vertical lobe and the endings in the retina and optic lobe, both of which are derived from the retinal visual cells, have only agranular synaptic vesicles. The Golgi apparatuses of the median superior frontal perikarya have vesicles, approximately 4.3% of which are granulated. The amacrine Golgi apparatuses have 1.5% granulated vesicles. The visual cell Golgi apparatuses have virtually no dense-cored vesicles, only agranular ones. The question of the formation of dense-cored and agranular synaptic vesicles at the Golgi apparatus and their subsequent transport to the terminals are related to these observations.