COITUS INDUCED C FOS EXPRESSION IN BRAINSTEM

排卵是控制生育和治疗的主要目标 不孕 自然排卵是由大量释放的 下丘脑促性腺激素释放激素（GnRH），这是触发 通过其他神经肽和神经递质的相互作用 （去甲肾上腺素、神经肽Y、β-内啡肽、甘丙肽和γ-内啡肽） 氨基丁酸）。 这些神经化学物质存在于下丘脑中 和/或脑干，但他们的确切位置和机械步骤， 调节GnRH分泌目前是未知的。 我们假设 在GnRH激增期间，基因转录的幅度和 表达这些化学物质的神经元的翻译也应该 增加 为了验证这一假设，我们利用了 早期癌基因c-fos作为基因启动的标志物 转录过程。 我们推断在排卵前 GnRH激增，这些脑干区域显示c-fos mRNA增加， 表达可能含有神经元， 促性腺激素释放激素激增诱导化学物质的分泌。 母兔是一只 理想的模型来测试这一假设，因为确切的时间， 排卵性GnRH激增可以通过与男性性交来控制。 我们有 显示性交诱导的去甲肾上腺素（NE） 和GnRH在10-30分钟内开始，并在240分钟后完成 交配 因此，开始了一项实验， 处死家兔，用多聚甲醛固定其脑组织 输注前和输注后30 min、60 min、120 min和240 min 交媾 交配的雄性大脑也以类似的时间间隔收集 用作对照，因为性交不会诱导NE/GnRH增加 在雄鹿。 c-fos mRNA的表达通过免疫组织化学方法检测。 原位杂交技术在下丘脑和 脑干 在性交后60分钟的雌性脑干中（ 其他时间尚未检查），几个去甲肾上腺素能 神经元区域，包括外侧被盖（A1）， 孤束（A2）和蓝斑（A6），显示 c-fos mRNA表达增强。 此外，介词的核心 hypoglosic和paragigantocellular核，只有两个尾侧 支配蓝斑的核团也表达c-fos， 交配雌虫的含量高于交配雄虫。 几 下丘脑中的区域，包括弓状和室旁 神经肽Y、GnRH和甘丙肽神经元所在的核， 也表现出c-fos表达，虽然在数量上的差异， c-fos在这些区域的表达在男女之间没有显著差异， 很明显 这些初步结果表明，含有c-fos的 神经元可能有助于识别细胞和化学物质参与 早期激活性交诱导的排卵前GnRH峰。 最终，我们希望将这些研究扩展到灵长类动物， 在猴子（Macaca mulatta）身上观察到， 脑干蓝斑去甲肾上腺素基因的表达， 下丘脑去甲肾上腺素释放大量增加 在雌激素驱动的排卵前GnRH之前和期间 浪涌。 我们推测排卵障碍和生殖能力下降 慢性应激患者或绝经期妇女的表现 可能反映去甲肾上腺素能基因表达和活性的损伤。

Ovulation is a major target for controlling fertility and treating infertility. Natural ovulation is initiated by a surge release of hypothalamic gonadotropin-releasing hormone (GnRH), which is triggered via interaction of other neuropeptides and neurotransmitters (norepinephrine, neuropeptide Y, -endorphin, galanin and gamma aminoabutyric acid). These neural chemicals exist in the hypothalamus and/or brainstem, but their exact locations and mechanistic steps in regulating GnRH secretion is currently unknown. We hypothesize that during the GnRH surge, the magnitude of gene transcription and translation in neurons expressing these chemicals should also increase. To test this hypothesis, we utilized the expression of the early oncogene, c-fos, as a marker for the onset of gene transcriptional processes. We reasoned that during the preovulatory GnRH surge, those brainstem areas that show an increase in c-fos mRNA expression probably contain neurons that secrete, or influence secretion of, GnRH surge-inducing chemicals. The female rabbit is an ideal model to test this hypothesis because the exact timing of the ovulatory GnRH surge can be controlled by coitus with a male. We have shown that the coitally induced secretion of both norepinephrine (NE) and GnRH begins within 10-30 min and is complete by 240 min after copulation. An experiment was initiated, therefore, in which female rabbits were killed and their brains fixed by paraformaldehyde infusion at times before and 30 min, 60 min, 120 min and 240 min after coitus. Mated male brains were also collected at similar intervals for use as controls because coitus does not induce NE/GnRH increases in the buck. Expression of c-fos mRNA is being examined by the in situ hybridization technique in 20 m sections of the hypothalamus and brainstem. In the female brainstem at 60 min after coitus (tissues at other times have not yet been examined), several noradrenergic neuronal areas, including the lateral tegmentum (A1), the nucleus of the solitary tract (A2) and the locus coeruleus (A6), exhibited enhanced c-fos mRNA expression. Moreover, the nucleus of prepositus hypoglossy and the paragigantocellular nucleus, the only two caudal nuclei that innervate the locus coeruleus, also expressed c-fos in higher content in the mated female than in the mated male. Several areas in the hypothalamus, including the arcuate and paraventricular nuclei where neuropeptide Y, GnRH and galanin neurons are located, also exhibited c-fos expression, although differences in the magnitude of c-fos expression in these areas between males and females were not apparent. These preliminary results suggest that c-fos containing neurons may be useful in identifying cells and chemicals involved in early activation of the coitus-induced preovulatory GnRH surge. Ultimately, we hope to extend these studies to primates because we have observed in the monkey (Macaca mulatta) that a 10-fold increase in norepinephrine gene expression in the brainstem locus coeruleus and a massive increase in hypothalamic norepinephrine release occur immediately before and during the estrogen-driven preovulatory GnRH surge. We speculate that disrupted ovulation and reduced reproductive performance in patients under chronic stress or in menopausal women may reflect a lesion in noradrenergic gene expression and activity.