Both are forms of short-range cell signaling. The signaling molecules are released from one cell and act on adjacent cells within a relatively short distance. They also both rely on chemical messengers to transmit signals between cells. For synaptic signaling, the chemical messengers are neurotransmitters. In paracrine signaling, the chemical messengers are hormones. Additionally, in both types of signaling, the target cells possess specific receptors which recognize and bind to signaling molecules.