title: Subcutaneous transplantation promotes organ formation of the fetal rat urogenital sinus.
abstract: The aim of this study is to develop a novel experimental model of the subcutaneous transplantation of fetal urogenital sinus (UGS) into normal and castrated adult male rats for the pathophysiological investigation of the normal and developing prostate. Fetal UGS obtained from 20-day-old male rat embryos was subcutaneously transplanted into 7-week-old normal and castrated male rats. We observed the growth pattern, histopathological characteristics and immunohistochemical localization of cytokeratin 5 (CK 5), cytokeratin 8 (CK 8) and androgen receptor (AR) in the transplanted tissues. Almost all of the transplanted UGS organs gradually increased in weight over time in the non-castrated recipient animals, and the histopathological observations and immunohistochemical analysis of CK 5 and CK 8 revealed that the morphological changes in the tissues were in accordance with the features of normal prostate development. The histological characteristics included glandular epithelial dominant and stromal dominant area, with an increase in the glandular epithelial dominant areas over time and resemblance among a portion of the transplanted tissues within a certain period during the developmental course to the histopathology of human benign prostatic hyperplasia (BPH). The effects of androgens and resemblance in the immunohistochemical localization pattern changes in AR to that observed in the normal differentiating rat prostate were also noted. We conclude that the subcutaneous space provides an adequate microenvironment for UGS growth.
authors: Division of Microscopic and Developmental Anatomy, Department of Anatomy, Kurume University School of Medicine, Kurume, Fukuoka, Japan; Department of Urology, Kurume University School of Medicine, Kurume, Fukuoka, Japan. Electronic address: uemura_keiichirou@kurume-u.ac.jp.
authors: Kei-ichiro
authors: K
authors: Uemura
authors: Division of Microscopic and Developmental Anatomy, Department of Anatomy, Kurume University School of Medicine, Kurume, Fukuoka, Japan.
authors: Keisuke
authors: K
authors: Ohta
authors: Division of Microscopic and Developmental Anatomy, Department of Anatomy, Kurume University School of Medicine, Kurume, Fukuoka, Japan.
authors: Tomonoshin
authors: T
authors: Kanazawa
authors: Department of Urology, Kurume University School of Medicine, Kurume, Fukuoka, Japan.
authors: Tokumasa
authors: T
authors: Hayashi
authors: Division of Microscopic and Developmental Anatomy, Department of Anatomy, Kurume University School of Medicine, Kurume, Fukuoka, Japan.
authors: Ryuichiro
authors: R
authors: Tanoue
authors: Division of Microscopic and Developmental Anatomy, Department of Anatomy, Kurume University School of Medicine, Kurume, Fukuoka, Japan.
authors: Munetake
authors: M
authors: Yoshitomi
authors: Division of Microscopic and Developmental Anatomy, Department of Anatomy, Kurume University School of Medicine, Kurume, Fukuoka, Japan.
authors: Shingo
authors: S
authors: Hirashima
authors: Department of Urology, Kurume University School of Medicine, Kurume, Fukuoka, Japan.
authors: Shigetaka
authors: S
authors: Suekane
authors: Department of Urology, Kurume University School of Medicine, Kurume, Fukuoka, Japan.
authors: Kei
authors: K
authors: Matsuoka
authors: Department of Urology, Kurume University School of Medicine, Kurume, Fukuoka, Japan.
authors: Tsukasa
authors: T
authors: Igawa
authors: Division of Microscopic and Developmental Anatomy, Department of Anatomy, Kurume University School of Medicine, Kurume, Fukuoka, Japan.
authors: Kei-ichiro
authors: K
authors: Nakamura
mesh_terms: D000818:Animals; D005260:Female; D005333:Fetus / Q000378:metabolism; D007150:Immunohistochemistry; D008297:Male; D038081:Organogenesis / Q000235:genetics / Q000502:physiology; D011247:Pregnancy; D051381:Rats; D017207:Rats, Sprague-Dawley; D014566:Urogenital System / Q000196:embryology*
keywords: Ectopic development; Subcutaneous space; Transplant; Urogenital sinus