Shughrue P J, Stumpf W E, Sar M, Elger W, Schulze P E
Department of Cell Biology and Anatomy, University of North Carolina, Chapel Hill 27599.
Endocrinology. 1989 Jan;124(1):333-8. doi: 10.1210/endo-124-1-333.
The distribution of progestin target sites in the brain and pituitary of estrogen-primed 20-day-old fetal mice was investigated by thaw-mount autoradiography. Three pregnant mice were each implanted sc with a Silastic tube containing estrogen on day 17 and ovariectomized on day 19 of gestation. Twenty-four hours after ovariectomy 10 fetuses (5 males and 5 females) were collected and each injected sc with 0.33 microgram/100 g BW [125I]progestin (SA, 2200 Ci/mM). For competition, two additional fetuses were injected with 20 micrograms R5020 1 h before (Z)-17 beta-hydroxy-17 alpha-(2[125I]iodovinyl)4-estren-3-one [( 125I]Progestin) to demonstrate that nuclear uptake and retention of radioactivity were specific for progestin. Two hours after injection of [125I]Progestin all fetuses were mounted, frozen, and sectioned in a cryostat. After 1-37 days of exposure, sections were developed and scanned for labeled cells. Cells with nuclear concentration were found in the male and female preoptic area, within certain nuclear groups in the basal hypothalamus, in the central gray of the midbrain, and in the pituitary. No labeling was detected in the cortex or amygdala. The results indicate that cells in certain regions of the brain and pituitary express progestin receptors at the end of gestation and suggest that progesterone is important for the normal development of these cells.
通过冷冻切片放射自显影法研究了雌激素预处理的20日龄胎鼠大脑和垂体中孕激素靶位点的分布。三只怀孕小鼠在妊娠第17天分别皮下植入含雌激素的硅橡胶管，并在妊娠第19天进行卵巢切除。卵巢切除24小时后，收集10只胎儿（5只雄性和5只雌性），每只皮下注射0.33微克/100克体重的[125I]孕激素（比活度，2200居里/毫摩尔）。为了进行竞争实验，另外两只胎儿在注射(Z)-17β-羟基-17α-(2-[125I]碘乙烯基)-4-雌甾烯-3-酮([125I]孕激素)前1小时注射20微克R5020，以证明放射性的核摄取和保留对孕激素具有特异性。注射[125I]孕激素两小时后，将所有胎儿固定、冷冻，并在低温恒温器中切片。曝光1 - 37天后，对切片进行显影并扫描标记细胞。在雄性和雌性视前区、下丘脑基底的某些核团、中脑中央灰质和垂体中发现了有核浓缩的细胞。在皮质或杏仁核中未检测到标记。结果表明，大脑和垂体某些区域的细胞在妊娠末期表达孕激素受体，提示孕激素对这些细胞的正常发育很重要。
