title: Ultrastructure of the lamina propria of the human ductuli efferentes and ductus epididymidis.
abstract: The cellular and connective tissue constituents of the lamina propria of the ductuli efferentes and the ductus epididymidis of prepubescent, adult and senescent men were studied by means of electron microscopy. Layers of contractile cells showing features of smooth muscle cells, alternate with interstitial layers of connective tissue fibers. Additionally to collagenous fibers, in the interstitial layers three types of elastic system fibers, oxytalan, elaunin and elastic, were evident, differing by their varying amount of elastin. Oxytalan fibers, lacking the amorphous component elastin, were present in almost all intercellular spaces along the excurrent duct system, closely related to the contractile cells. They were the only type of elastic system fibers recognizable in the prepubescent epididymal lamina propria. However, in the adult and senescent men, elastin deposits were observed in the middle and outer layers of the lamina propria. In these cases the elaunin and elastic fibers appeared to increase with the gradual proximo-distal thickening of the subepithelial coat of contractile cells. In senescent men, only in few cases the epididymal lamina propria showed some alterations. It is suggested that these changes are not related to age but more likely to the state of individual testicular function. The functional significance of the special architecture of the epididymal lamina propria is discussed.
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000375:Aging; D002648:Child; D003238:Connective Tissue / Q000648:ultrastructure; D003285:Contractile Proteins / Q000378:metabolism; D004547:Elastic Tissue / Q000378:metabolism / Q000648:ultrastructure; D004549:Elastin / Q000378:metabolism; D004822:Epididymis / Q000254:growth & development / Q000378:metabolism / Q000648:ultrastructure*; D016326:Extracellular Matrix Proteins; D006801:Humans; D008297:Male; D008854:Microscopy, Electron; D008875:Middle Aged; D009130:Muscle, Smooth / Q000648:ultrastructure; D000072260:RNA Splicing Factors
chemical_list: D003285:Contractile Proteins; D016326:Extracellular Matrix Proteins; D000072260:RNA Splicing Factors; C049028:elaunin; C016598:microfibrillar protein; D004549:Elastin