title: Ultrastructural localization of the NADPH-diaphorase activity in the Leydig cells of aging mice.
abstract: Recently, it has been shown that nitric oxide may inhibit the Leydig cell steroidogenesis. The present paper describes, by means of NADPH-diaphorase histochemistry, the ultrastructural localization of the enzyme nitric oxide synthase in the Leydig cells of young adult and aging mice. In the young adult mice, the enzymatic reaction was mainly located in the mitochondria and in some clustered cisternae of the smooth endoplasmic reticulum. The nuclear envelope was faintly labeled. In the aging mice, most Leydig cells showed an enhanced enzymatic reaction. Labeled mitochondria were increased in number, and labeled areas of the smooth endoplasmic reticulum were more numerous and extended. In addition, a strong enzymatic reaction was recognized in the nuclear envelope. We conjecture that the impaired steroidogenesis observed in the testis of aging mammals might, at least in part, depend on the increased nitric oxide production in the Leydig cells.
authors: Dipartimento di Morfologia Umana e Biologia Applicata, Facoltà di Medicina e Chirurgia, Università degli Studi di Pisa, Via Roma, 55-56126 Pisa, Italy. rruffoli@anist.med.unipi.it
authors: R
authors: R
authors: Ruffoli
authors: M A
authors: MA
authors: Giambelluca
authors: F
authors: F
authors: Giannessi
authors: P
authors: P
authors: Soldani
authors: L
authors: L
authors: Grasso
authors: M
authors: M
authors: Gasperi
authors: F
authors: F
authors: Giannessi
mesh_terms: D000375:Aging; D000818:Animals; D018871:Endoplasmic Reticulum, Smooth / Q000201:enzymology; D007985:Leydig Cells / Q000201:enzymology* / Q000648:ultrastructure*; D008297:Male; D051379:Mice; D008854:Microscopy, Electron; D008928:Mitochondria / Q000201:enzymology; D009252:NADPH Dehydrogenase / Q000032:analysis*; D019001:Nitric Oxide Synthase / Q000032:analysis; D009685:Nuclear Envelope / Q000201:enzymology
chemical_list: D019001:Nitric Oxide Synthase; D009252:NADPH Dehydrogenase