(1) Protein kinase C is a family of phospholipid-dependent protein kinases which are involved in the regulation of diverse cellular functions. (2) Evidence is emerging that certain general anesthetics can stimulate the activity of protein kinase C by interacting with the regulatory domain of the enzyme, possibly with the diacylglycerol binding sites. Anesthetics also potentiate activation-dependent down-regulation of the enzyme. (3) A role for PKC in the mediation and or modulation of the cellular effects of general anesthetics is a potential molecular target for anesthetic action.