Bethea C L, Streicher J M, Mirkes S J, Sanchez R L, Reddy A P, Cameron J L
Division of Reproductive Sciences, Oregon National Primate Research Center, 505 Northwest 185th Avenue, Beaverton, OR 97006, USA.
Neuroscience. 2005;132(1):151-66. doi: 10.1016/j.neuroscience.2004.11.022.
Female cynomolgus monkeys exhibit different degrees of reproductive dysfunction with moderate metabolic and psychosocial stress. In this study, the expression of four genes pivotal to serotonin neural function was assessed in monkeys previously categorized as highly stress resistant (n=3; normal menstrual cyclicity through two stress cycles), medium stress resistant (n=5; ovulatory in the first stress cycle but anovulatory in the second stress cycle), or low stress resistant (i.e. stress-sensitive; n=4; anovulatory as soon as stress is initiated). In situ hybridization and quantitative image analysis was used to measure mRNAs coding for SERT (serotonin transporter), 5HT1A autoreceptor, MAO-A and MAO-B (monoamine oxidases) at six levels of the dorsal raphe nucleus (DRN). Optical density (OD) and positive pixel area were measured with NIH Image software. In addition, serotonin neurons were immunostained and counted at three levels of the DRN. Finally, each animal was genotyped for the serotonin transporter long polymorphic region (5HTTLPR). Stress sensitive animals had lower expression of SERT mRNA in the caudal region of the DRN (P<0.04). SERT mRNA OD in the caudal DRN was positively correlated with serum progesterone during a pre-stress control cycle (P<0.0007). 5HT1A mRNA OD signal tended to decline in the stress-sensitive group, but statistical difference between averages was lacking in analysis of variance. However, 5HT1A mRNA signal was positively correlated with control cycle progesterone (P<0.009). There was significantly less MAO-A mRNA signal in the stress-sensitive group (P<0.007) and MAO-A OD was positively correlated with progesterone from a pre-stress control cycle (P<0.007). MAO-B mRNA exhibited a similar downward trend in the stress-sensitive group. MAO-B OD also correlated with control cycle progesterone (P<0.003). There were significantly fewer serotonin neurons in the stress-sensitive group. All animals contained only the long form of the 5HTTLPR. Thus, all serotonin-related mRNAs examined in the dorsal raphe to date were lower (SERT, MAO-A) or exhibited a lower trend (5HT1A, MAO-B) in the stress sensitive animals, which probably reflects the lower number of serotonin neurons present.
雌性食蟹猴在面临中度代谢和心理社会压力时会表现出不同程度的生殖功能障碍。在本研究中，对先前被分类为高应激抗性（n = 3；在两个应激周期中月经周期正常）、中度应激抗性（n = 5；在第一个应激周期有排卵，但在第二个应激周期无排卵）或低应激抗性（即应激敏感；n = 4；一旦开始应激就无排卵）的猴子，评估了对血清素神经功能至关重要的四个基因的表达。采用原位杂交和定量图像分析技术，在中缝背核（DRN）的六个水平上测量编码血清素转运体（SERT）、5HT1A自身受体、单胺氧化酶A（MAO-A）和单胺氧化酶B（MAO-B）的mRNA。使用NIH Image软件测量光密度（OD）和阳性像素面积。此外，对DRN的三个水平上的血清素神经元进行免疫染色并计数。最后，对每只动物的血清素转运体长多态性区域（5HTTLPR）进行基因分型。应激敏感的动物在DRN尾侧区域的SERT mRNA表达较低（P < 0.04）。在应激前的对照周期中，DRN尾侧的SERT mRNA OD与血清孕酮呈正相关（P < 0.0007）。在应激敏感组中，5HT1A mRNA OD信号有下降趋势，但方差分析中平均值之间缺乏统计学差异。然而，5HT1A mRNA信号与对照周期孕酮呈正相关（P < 0.009）。应激敏感组中MAO-A mRNA信号明显较少（P < 0.007），且MAO-A OD与应激前对照周期的孕酮呈正相关（P < 0.007）。在应激敏感组中，MAO-B mRNA也呈现类似的下降趋势。MAO-B OD也与对照周期孕酮相关（P < 0.003）。应激敏感组中的血清素神经元明显较少。所有动物仅含有5HTTLPR的长形式。因此，迄今为止在中缝背核中检测到的所有与血清素相关的mRNA在应激敏感动物中较低（SERT、MAO-A）或呈现较低趋势（5HT1A、MAO-B），这可能反映了血清素神经元数量较少。
