title: The fine structure of the testis wall in Salamandra salamandra (L.) (Amphibia, Urodela).
abstract: In mature fire salamander testes examined in early spring, smooth muscle cells can as a rule be observed in the connective tissue which underlies the peritoneal epithelium covering the testis. These smooth muscle cells show a variable degree of differentiation that ranges from fibroblast-like cells in the cranial immature parts of the testis to contracted smooth muscle cells with bundles of myofilaments in the caudal (regressive) glandular tissue, indicating a close relationship to the spermatogenic cycle. The monolayered peritoneal epithelium consists of one cell type only, which is extremely flattened in most parts of the testis and columnar in the glandular tissue. The height of the epithelium may partly be due to the non-contracted resp. contracted state of the underlying muscle cells. The muscle cells are possibly involved in sperm discharge.
mesh_terms: D000818:Animals; D003094:Collagen / Q000032:analysis; D004848:Epithelium / Q000648:ultrastructure; D005347:Fibroblasts / Q000648:ultrastructure; D008297:Male; D009119:Muscle Contraction; D009130:Muscle, Smooth / Q000648:ultrastructure; D012454:Salamandra / Q000033:anatomy & histology*; D013094:Spermatozoa / Q000648:ultrastructure; D013737:Testis / Q000502:physiology / Q000648:ultrastructure*
chemical_list: D003094:Collagen