Sar M
Department of Cell Biology and Anatomy, University of North Carolina, Chapel Hill 27599.
Endocrinology. 1988 Aug;123(2):1110-8. doi: 10.1210/endo-123-2-1110.
The anatomical distribution of progestin-concentrating cells in rat brain was investigated by thaw-mount autoradiography. Fifteen 23-day-old ovariectomized and adrenalectomized female Holtzman rats were injected sc with 5 micrograms 17 beta-estradiol in oil/100 g BW daily for 4 days. On the fifth day, all animals were injected iv with 1 microgram/100 g BW [3H]ORG.2058, a synthetic progestin. The animals were killed after 30 or 60 min, and the brains were frozen and processed for autoradiography. Nuclear concentration of radioactivity was found in certain cells of the forebrain and midbrain and was prevented by prior injection (15 min) of excess unlabeled ORG.2058. In the preoptic-septal region, progestin-labeled neurons were observed in the nucleus (n.) septi lateralis, n. interstitialis striae terminalis, n. preopticus medialis, n. preopticus lateralis, n. preopticus periventricularis, and n. preopticus suprachiasmaticus. In the hypothalamus, labeled neurons were seen in n. periventricularis hypothalami, n. arcuatus hypothalami, n. ventromedialis hypothalami, n. dorsomedialis hypothalami, n. premammillaris ventralis, n. premammillaris dorsalis, and lateral hypothalamus. In the extrahypothalamic region, a few labeled cells were found in the central, medial, and cortical nuclei of the amygdala, the organum subforniculare, the lateral geniculate nucleus, the parietal and entorhinal cortex, and the central gray of the midbrain. Some of the progestin-concentrating cells were characterized with combined autoradiography and immunocytochemistry. Tyrosine hydroxylase-containing cells of the arcuate nucleus and the hypothalamic periventricular nucleus (group A12) showed nuclear concentration of radioactivity. Tyrosine hydroxylase cells in groups A11, A13, and A14; the substantia nigra (group A9); and the ventral tegmental area (group A10) did not show nuclear concentration of [3H]ORG.2058. The autoradiographic study demonstrates specific progestin-binding sites in nuclei of neurons in select areas of the rat brain. The results of combined autoradiography and immunocytochemistry suggest, for the first time, a direct action of progestin on tuberoinfundibular dopaminergic neurons.
通过冷冻切片放射自显影术研究了大鼠脑中孕激素浓缩细胞的解剖分布。15只23日龄的去卵巢和肾上腺切除的雌性霍尔茨曼大鼠，每天皮下注射5微克溶于油中的17β-雌二醇/100克体重，共注射4天。在第5天，所有动物静脉注射1微克/100克体重的[3H]ORG.2058，一种合成孕激素。30或60分钟后处死动物，将脑冷冻并进行放射自显影处理。在前脑和中脑的某些细胞中发现了放射性核素的核浓缩，并且预先注射（15分钟）过量的未标记ORG.2058可阻止这种情况。在视前-隔区，在外侧隔核、终纹床核间质性核、内侧视前核、外侧视前核、室周视前核和视交叉上视前核中观察到孕激素标记的神经元。在下丘脑，在室周下丘脑核、弓状下丘脑核、腹内侧下丘脑核、背内侧下丘脑核、乳头体前腹侧核、乳头体前背侧核和外侧下丘脑中看到标记的神经元。在丘脑外区域，在杏仁核的中央、内侧和皮质核、穹窿下器、外侧膝状体核、顶叶和内嗅皮质以及中脑中央灰质中发现了一些标记细胞。一些孕激素浓缩细胞通过放射自显影术和免疫细胞化学相结合进行了表征。弓状核和下丘脑室周核（A12组）中含酪氨酸羟化酶的细胞显示出放射性核素的核浓缩。A11、A13和A14组中的酪氨酸羟化酶细胞；黑质（A9组）；以及腹侧被盖区（A10组）未显示[3H]ORG.2058的核浓缩。放射自显影研究证明了大鼠脑特定区域神经元核中存在特异性孕激素结合位点。放射自显影术和免疫细胞化学相结合的结果首次表明孕激素对结节漏斗多巴胺能神经元有直接作用。
