A "dense core vesicle" is a specialized and membrane-bound organelle found within cells, particularly in neurons or endocrine cells. It is typically characterized by its dense interior contents and its ability to secrete various signaling molecules, such as hormones or neurotransmitters.
These vesicles are formed through a process called vesicle budding, in which a small portion of the cell's plasma membrane pinches off to form a pocket that matures into a distinct vesicle. Dense core vesicles are larger and more complex than other vesicles, such as synaptic vesicles.
Structurally, dense core vesicles are composed of a lipid bilayer membrane that encloses a dense and granular core. The contents of the core consist of a variety of substances, including peptides, hormones, growth factors, enzymes, and other signaling molecules. These vesicles are distinguished by their ability to store and transport such substances to various parts of the cell or for secretion outside the cell.
Dense core vesicles are involved in various important biological processes, such as cell-to-cell communication and regulation of physiological functions. Upon stimulation or neuronal activity, these vesicles undergo exocytosis, during which the vesicle fuses with the plasma membrane, releasing its contents into the extracellular space or target cells. This release of signaling molecules enables the transmission of information, initiation of cellular responses, and regulation of physiological processes both within and between cells.
Overall, dense core vesicles play a crucial role in the intricate communication network of cells and are essential for the proper functioning of the nervous system and endocrine system.
