REPRODUCTIVE SIGNALLING IN BRAINSTEM

精选的脑神经元活动不足会导致许多 疾病，包括不孕不育。例如，生殖 功能不全是暴饮暴食患者的常见症状 毒品问题，这两者都可能使人上瘾。解剖学和 肥胖、药物成瘾与肥胖的生理学联系 不孕症是未知的，尽管三种神经化学物质，即， 神经肽Y(NPY)、去甲肾上腺素转运体(Net)和 可能与去甲肾上腺素(NE)有关。三个大脑中的每个 物质可影响促性腺激素释放的分泌 荷尔蒙(GnRH)，是一种十肽，是 繁衍)。NPY和NE改变进食行为，Net和NE改变饮食行为 沉溺于毒瘾。我们假设三者的整合 神经化学物质存在于脑干中，我们利用兔子作为 识别分布的初始模型(在灵长类研究之前) 含有NPY、Net和酪氨酸羟化酶(TH， 去甲肾上腺素合成限速酶(MRNAs)的原位检测 杂交。克隆了兔特异性Net和TH基因片段 逆转录-聚合酶链式反应及其相互作用 测定了核苷酸序列。这两个cDNA(以及一个 以人NPY基因片段为探针，与 通过兔脑全长的各个mRNA 均以20Fm厚切片。连续切片也被染色 对于多巴胺-羟化酶(D-H，一种蛋白质酶)的存在 NE合成的特异性)通过免疫细胞化学标记脑干NE 细胞。数据表明，虽然Net和THRNA位于 包括蓝斑(LC)在内的所有D H阳性区域 主要由NE细胞组成)，在LC中未观察到NPY mRNA 细胞。然而，外侧被盖和孤束核 TRAIL含有表达所有这三种基因的细胞。这些结果 为潜在的NPY、Net和NE整合提供解剖学基础 可能调节进食行为的外周和中枢信号， 吸毒成瘾和生殖能力。

Inadequate activities in select brain neurons can cause many diseases, including infertility. For example, reproductive incompetence is a frequent symptom in patients with over-eating and drug problems, both of which can be addictive. The anatomical and physiological associations between obesity, drug addiction and infertility are unknown, although three neurochemicals, i.e., neuropeptide Y (NPY), norepinephrine transporter (NET) and norepinephrine (NE), are likely involved. Each of the three brain substances can influence the secretion of gonadotropin-releasing hormone (GnRH, a deca-peptide that is a key regulator of reproduction). NPY and NE alter eating behavior and NET and NE are involved in addiction. We hypothesize that integration of the three neurochemicals occurs in the brainstem and we utilized the rabbit as an initial model (before primate studies) to identify the distribution of brainstem cells containing NPY, NET and tyrosine hydroxylase (TH, the rate-limiting enzyme for NE synthesis) mRNAs by in situ hybridization. Specific rabbit NET and TH cDNA fragments were cloned by reverse transcription-polymerase chain reaction and their nucleotide sequences were determined. These two cDNA (as well as a human NPY cDNA) fragments were used as probes for hybridization with respective mRNAs through the entire length of rabbit brainstems that were sectioned at 20 fm thickness. Serial sections were also stained for the presence of dopamine- -hydroxylase (D H, a protein enzyme specific for NE synthesis) by immunocytochemistry to mark brainstem NE cells. The data suggest that while NET and TH mRNAs were located in all D H-positive areas including the locus coeruleus (LC, an area that consists of predominantly NE cells), NPY mRNA was not observed in LC cells. However, the lateral tegmentum and the nucleus of the solitary tract contained cells that expressed all three genes. These results provide an anatomical basis for potential NPY, NET and NE integration of peripheral and central signals that may modulate eating behavior, drug addiction and reproductive performance.