Autoradiographic study on localization of progestin target cells in the chicken testes

Abstract

オートラジオグラフィーによって, 25-70日齢の未熟鶏および120日齢の成鶏の精巣の細胞成分におけるプロジェスチン(P)の局在と濃度を調査した.精巣の凍結切片標本を放射能で標識した合成P (3H-Promegestoneまたは3H-R5020)溶液中で培養した後, 常法通りオートラジオグラフィーを行い, 組織または細胞上の黒化銀粒子数を算定して, 放射活性の強さまたはP濃度の指標とした.その結果, 1)精細管上皮と間質細胞に放射活性の特異的集中が見られた.2)放射活性の強さは動物の日齢によって変動した.25, 70および120日齢で高く, 50日齢で低かった.3)細胞内のP濃度は動物をあらかじめエストロジェンで処置しておくと増強した.4)放射活性の強さは間質細胞よりも精細管上皮で高かった.しかし, 凍結切片標本では高放射活性を示す細胞の同定は困難であった.以上の結果から, 成長期のニワトリ精巣の精細管壁と間質にPレセプター含有細胞が存在することが示唆される

Using an autoradiographic technique, the localization and concentration of progestin (P) in cell constituents of testes from the immature 25-to-70-day-old and mature 120-day-old chickens were investigated. After incubation of the frozen tissue sections with 3H-Promegestone (R5020), a synthetic P, specific radioactivity, was found in the seminiferous epithelium and interstitium in all the animals in the presence or in the absence of various non-radioactive steroids, and the intensity of radioactivity differed with age: high in 25-, 70-and 120-day-old chickens, and low in 50-day-old chickens. Estrogen treatment enhanced the intensity of radioactivity in the cells at all ages. The concentration of radioactivity was higher in the seminiferous epithelium than in the interstitial cells. In the frozen tissue sections, it was not possible to identify the kind of cell taking up the high amount of radioactivity. These results indicate that the testes from chicken during their growing stages contain cell constituents that specifically bind P.