[Role of Gap junctions in bone tissue]

Gap junctions are transmembrane channels, that connect the membranes of adjacent cells and are involved in the direct signal transmission between the cells. The intercellular communication involving this type of channels provides the proper functioning of tissues and organs. Gap junctions formation and synthesis of connexins is regulated by hormones, growth factors and signaling molecules. Gap junctions, located between osteoblasts, osteoclasts, and osteocytes, play a key role in the process of bone turnover, and therefore in the modeling and bone tissue regeneration. They also mediate the regulation of proliferation, differentiation and maturation of osteoblasts, as well as formation and activity of osteoclasts. This paper presents the current state of knowledge on the role of intercellular connections via Gap junctions in bone cells, with particular emphasis on the involvement of connexin 43, in the regulation of osteogenesis.