The role of extracellular ATP in the male reproductive tract.

In addition to its well established role as a neurotransmitter, extracellular ATP has been considered as a paracrine/autocrine factor, either released from sperm or epithelial cells, in the male reproductive tract and shown to play a versatile role in modulating various reproductive functions. This review summarizes the signal pathways through which ATP induces anion secretion by the epithelia of the epididymis, as well as its epithelium-dependent modulation of smooth muscle contraction of the vas deferens. Finally, the overall role of ATP in coordinating various reproductive events in the male genital tract is discussed.