. "Any intracellular signal transduction in which the signal is passed on within the cell via a second messenger; a small molecule or ion that can be quickly generated or released from intracellular stores, and can diffuse within the cell. Second-messenger signaling includes production or release of the second messenger, and effectors downstream of the second messenger that further transmit the signal within the cell." . . "second-messenger-mediated signaling" . "second messenger mediated signaling" . "second messenger mediated signalling" . "second messenger-mediated signaling" . "second messenger-mediated signalling" . "second-messenger-mediated signalling" . . . . . . .