Mesenchymal cells are continually stimulated by a wide spectrum of bio
logical mediators. These mediators bind to receptors on the cell surfa
ce and initiate a cascade of signaling events. The initial signal tran
sduction pathways known to be stimulated in mesenchymal cells include
phospholipase C, phospholipase D, phospholipase A(2), adenylate cyclas
e, receptor tyrosine kinases, and receptor serine/threonine kinases. T
hese pathways are reviewed and specific applications for therapeutic i
ntervention in wound healing and regenerative therapy in the periodont
ium are discussed.