title: The relevance of spontaneous- and chemically-induced alterations in testicular germ cell apoptosis to toxicology.
abstract: Elimination of germ cells via apoptosis occurs spontaneously under normal physiologic conditions and is often heightened after chemical-induced testicular injury. Though many different apoptosis-related elements have been identified in the testis, the molecular and cellular mechanisms that regulate germ cell apoptosis are not thoroughly understood. In this review, the role of germ cell apoptosis in spermatogenesis and possible key regulators of apoptosis is described. The involvement of the Fas-signaling pathway between Sertoli cells and germ cells is highlighted as a crucial paracrine-signaling mechanism that responds to both physiologic- or toxicant-induced declines in the supportive capacity of the testis and reduces the germ cell population accordingly.
authors.affiliation: Division of Pharmacology and Toxicology, College of Pharmacy, The University of Texas at Austin, Austin, TX, USA. john_richburg@mail.utexas.edu
authors.forename: J H
authors.initials: JH
authors.lastname: Richburg
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects / Q000502:physiology*; D006801:Humans; D008297:Male; D009498:Neurotoxins / Q000633:toxicity; D012708:Sertoli Cells / Q000187:drug effects / Q000502:physiology; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology; D013094:Spermatozoa / Q000187:drug effects / Q000502:physiology* / Q000528:radiation effects; D014116:Toxicology / Q000639:trends; D019014:fas Receptor / Q000187:drug effects / Q000502:physiology
chemical_list: D009498:Neurotoxins; D019014:fas Receptor