title: Assessment of testicular corticosterone biosynthesis in adult male rats.
abstract: Corticosterone is synthesized in the adrenal glands and is circulated throughout the body to perform regulatory functions in various tissues. The testis is known to synthesize and secrete testosterone and other androgens. We developed an accurate method to measure steroid content using liquid chromatography-mass spectrometry analysis. In the present study, significant levels of the precursor compounds of testosterone and corticosterone synthesis could be detected in rat testis using this method. After adrenalectomy, corticosterone remained in the blood and testicular tissue at approximately 1% of the amount present in the control testis. When the excised testicular tissue was washed and incubated with NADH, NADPH and progesterone, not only testosterone and its precursors but also 11-deoxycorticosterone and corticosterone were produced; the levels of 11-deoxycorticosterone and corticosterone increased with incubation time. The production rate of 11-deoxycorticosterone from progesterone was estimated to be approximately 1/20 that of 17-hydroxyprogesterone, and the corticosterone level was approximately 1/10 that of testosterone. These ratios coincided with those in the testicular tissue of the adrenalectomized rats, indicating that corticosterone was synthesized in the testis and not in the blood. A primary finding of this study was that corticosterone and testosterone were synthesized in a 1/10-20 ratio in the testis. It is concluded that corticosterone, which has various functions, such as the regulation of glycolysis and mediating spermatogenesis, is produced locally in the testis and that this the local production is convenient and functional to respond to local needs.
authors.affiliation: Laboratory of Veterinary Biochemistry, School of Veterinary Medicine, Rakuno Gakuen University Ebetsu, Hokkaido, Japan; Japan Meat Science & Technology Institute, Shibuya-ku, Tokyo, Japan.
authors.forename: Naoyuki
authors.initials: N
authors.lastname: Maeda
authors.affiliation: Laboratory of Veterinary Biochemistry, School of Veterinary Medicine, Rakuno Gakuen University Ebetsu, Hokkaido, Japan.
authors.forename: Sachi
authors.initials: S
authors.lastname: Tahata
authors.affiliation: Laboratory of Veterinary Biochemistry, School of Veterinary Medicine, Rakuno Gakuen University Ebetsu, Hokkaido, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Yagi
authors.affiliation: Japan Meat Science & Technology Institute, Shibuya-ku, Tokyo, Japan.
authors.forename: Emi
authors.initials: E
authors.lastname: Tanaka
authors.affiliation: Japan Meat Science & Technology Institute, Shibuya-ku, Tokyo, Japan.
authors.forename: Kanae
authors.initials: K
authors.lastname: Masu
authors.affiliation: Laboratory of Veterinary Biochemistry, School of Veterinary Medicine, Rakuno Gakuen University Ebetsu, Hokkaido, Japan.
authors.forename: Michiko
authors.initials: M
authors.lastname: Sato
authors.affiliation: Laboratory of Veterinary Biochemistry, School of Veterinary Medicine, Rakuno Gakuen University Ebetsu, Hokkaido, Japan.
authors.forename: Satoko
authors.initials: S
authors.lastname: Haeno
authors.affiliation: Laboratory of Veterinary Nutrition, School of Veterinary Medicine, Rakuno Gakuen University Ebetsu, Hokkaido, Japan.
authors.forename: Takenori
authors.initials: T
authors.lastname: Onaga
authors.affiliation: Laboratory of Veterinary Biochemistry, School of Veterinary Medicine, Rakuno Gakuen University Ebetsu, Hokkaido, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yokota
mesh_terms: D019326:17-alpha-Hydroxyprogesterone / Q000097:blood / Q000378:metabolism; D000315:Adrenalectomy / Q000379:methods; D000818:Animals; D003345:Corticosterone / Q000096:biosynthesis* / Q000097:blood*; D003900:Desoxycorticosterone / Q000097:blood / Q000378:metabolism; D008297:Male; D009243:NAD / Q000378:metabolism; D009249:NADP / Q000378:metabolism; D011374:Progesterone / Q000097:blood / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D013737:Testis / Q000378:metabolism*; D013739:Testosterone / Q000097:blood / Q000378:metabolism
chemical_list: D009243:NAD; D013739:Testosterone; D003900:Desoxycorticosterone; D011374:Progesterone; D009249:NADP; D019326:17-alpha-Hydroxyprogesterone; D003345:Corticosterone