'Paracrine' control of spermatogenesis

Spermatogenesis is a remarkably complex but precise process yielding highly differentiated haploid germ cells from diploid stem cells. Although many f actors have been implicated in the paracrine control of spermatogenesis, fu nctional proof is only available for a few regulators. Among those are andr ogens, growth factors and stem cell factor. Cell- and organ-specific gene-t argeting will provide important insights into the relevance of local factor s controlling male gametogenesis. As testicular communication frequently oc curs between rather remote cells and compartments, it is proposed that the term 'local' rather than 'paracrine' mediators/factors should be used, sinc e the latter term refers to communication amongst neighbouring cells land m ainly via diffusion).