Dense core vesicles in cerebral cortex of the human fetus.

The present study clearly demonstrates that by the 15th week of gestation dense core vesicles appear within the human cerebral cortex. These vesicles can be identified within axon cylinders, axon growth cones, and axon synaptic terminals. The role of these vesicles is speculative, yet, their very presence at this early fetal stage seems to reflect an advanced state of synaptic vesicle development.