User:Jhpbroeke/Large dense core vesicle

Large dense core vesicles (LDCV) are vesicles containing neuropeptides, amines, growth factors and hormones. Their name comes from the fact that, contrary to synaptic vesicles, LDCVs are big and contain a core that is electron-dense under the electron microscope. They are found in many cells, but are especially enriched in cells that secrete hormones such as chromaffin cells and beta cells. Neurons also have LDCVs, however not as many as synaptic vesicles.

Synthesis
LDCVs contain proteins that are synthesized in the endoplasmatic reticulum. Once the proteins have been synthesized, they are transported to the Golgi network where preprocessing takes place. The proteins then cluster and bud off, becoming a LDCV, which travels towards the periphery of the cell.

Transport
LDCVs are transported by motor proteins along the microtubial cytoskeleton towards the periphery of the cell. Research has shown that in neurons, LDCVs during transport halt when the neuron is activated. During transport, postprocessing of the cargo takes place, resulting in the final active content of the vesicle upon arrival at the release site.

Release
Once LDCVs have arrived at the site they are required, they require an increase in calcium in order to fuse with the membrane and release their cargo. Unlike synaptic vesicles, LDCVs require a relatively large activation of the cell to allow enough calcium to enter the cell before fusing.