T-type Ca2+ channels in spermatogenic cells and sperm.

Cell function is importantly regulated by the intracellular concentration of Ca(2+) ([Ca(2+)]i). Sperm development and function are deeply influenced by [Ca(2+)]i which is modulated amongst other ion transporters by plasma membrane Ca(2+) permeable channels. The presence and role of voltage-dependent Ca(2+) channels (CaV) of the T-type (CaV3) in sperm physiology have become a matter of debate in recent years. Though they are functionally present in later stages of development in spermatogenic cells and testicular sperm and their mRNAs and proteins detected from spermatogenic cells to mature mammalian spermatozoa, their currents have not been recorded in mature spermatozoa. This review critically summarizes the evidence for the involvement of CaV3 channels in sperm development and function.