title: Expression of L-histidine decarboxylase in mouse male germ cells.
abstract: Histamine synthesis in male reproductive tissues remains largely unknown. The interaction between stem cell factor and its receptor, c-Kit, has been found to be essential for the maturation of male germ cells and peripheral mast cells. Based on this analogy, we investigated the expression of histidine decarboxylase (HDC), the rate-limiting enzyme of histamine synthesis, in mouse male germ cells. Immunohistochemical analyses revealed that HDC is localized in the acrosomes of spermatids and spermatozoa. In the testis, epididymis, and spermatozoa, a significant amount of histamine and HDC activity were detected. W/W(V) mice, known to lack most of their germ cells in the seminiferous tubules, were found to lack HDC protein expression as well as HDC activity in the testis. An in vitro acrosome reaction induced by a calcium ionophore, caused the release of histamine from epididymal spermatozoa. Our observations indicate that histamine is produced in and released from the acrosomes.
authors.affiliation: Department of Physiological Chemistry, Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan.
authors.forename: Faizah
authors.initials: F
authors.lastname: Safina
authors.forename: Satoshi
authors.initials: S
authors.lastname: Tanaka
authors.forename: Mariko
authors.initials: M
authors.lastname: Inagaki
authors.forename: Kazuhito
authors.initials: K
authors.lastname: Tsuboi
authors.forename: Yukihiko
authors.initials: Y
authors.lastname: Sugimoto
authors.forename: Atsushi
authors.initials: A
authors.lastname: Ichikawa
mesh_terms: D020101:Acrosome Reaction; D000818:Animals; D015152:Blotting, Northern; D000001:Calcimycin / Q000494:pharmacology; D004822:Epididymis / Q000201:enzymology; D006640:Histidine Decarboxylase / Q000096:biosynthesis* / Q000378:metabolism; D015151:Immunoblotting; D007150:Immunohistochemistry; D007476:Ionophores / Q000494:pharmacology; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013087:Spermatids / Q000201:enzymology*; D013094:Spermatozoa / Q000201:enzymology*; D013737:Testis / Q000201:enzymology / Q000378:metabolism
chemical_list: D007476:Ionophores; D012333:RNA, Messenger; D000001:Calcimycin; D006640:Histidine Decarboxylase