H
Hiroaki Nitta
Researcher at University of Illinois at Urbana–Champaign
Publications - 11
Citations - 850
Hiroaki Nitta is an academic researcher from University of Illinois at Urbana–Champaign. The author has contributed to research in topics: Aromatase & Theca. The author has an hindex of 9, co-authored 11 publications receiving 817 citations.
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Journal ArticleDOI
Germ cells of the mouse testis express P450 aromatase
Hiroaki Nitta,David Bunick,Rex A. Hess,Lynn Janulis,Sean C. Newton,Clark F. Millette,Yoshio Osawa,Yutaka Shizuta,Katsumi Toda,Janice M. Bahr +9 more
TL;DR: It is concluded that germ cells are a site of estrogen synthesis in the adult mouse testis through the conversion of cytochrome P450 enzyme to estrogen.
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Seasonal changes in spermatogenesis and testicular steroidogenesis in the male black bear Ursus americanus
Toshio Tsubota,L. Howell-Skalla,Hiroaki Nitta,Y. Osawa,J. I. Mason,P. G. Meiers,Ralph A. Nelson,Janice M. Bahr +7 more
TL;DR: It is demonstrated that in the black bear seasonal changes in spermatogenesis are accompanied by changes in the immunolocalization of testicular steroidogenic enzymes that are correlated with changes in serum testosterone and oestradiol concentrations.
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Mouse Epididymal Sperm Contain Active P450 Aromatase Which Decreases as Sperm Traverse the Epididymis
Lynn Janulis,Rex A. Hess,David Bunick,Hiroaki Nitta,Sarah Janssen,Yoshio Asawa,Janice M. Bahr +6 more
TL;DR: It is concluded that sperm can synthesize estrogen and that the synthesis of estrogen by sperm present in the efferent ductules and caput epididymis could be important in the process of sperm maturation.
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Rooster testicular germ cells and epididymal sperm contain P450 aromatase.
TL;DR: It is concluded that rooster testicular germ cells and epididymal sperm are sites for the synthesis of estrogen, a potential regulator or modulator of germinal epithelium in the testis and the epithelia of the epididcyal region of the avian species.
Journal ArticleDOI
Multiple steroidogenic cell populations in the thecal layer of preovulatory follicles of the chicken ovary
TL;DR: A multiple cell theory for steroidogenesis in the thecal layer of preovulatory follicles of the chicken ovary is proposed which states that interstitial cells in theTheca interna produce progestins and androgens, fibroblasts in the Theca externa may function as an additional site for the conversion of progestin to androgen, and aromatase cells inthe thecaExterna require androgens as substrate to produce estrogens.