Rassnick S, Hoffman G E, Rabin B S, Sved A F
Department of Neuroscience, Brain, Behavior and Immunity Center, University of Pittsburgh, PA 15260, USA.
Neuroscience. 1998 Jul;85(1):259-68. doi: 10.1016/s0306-4522(97)00574-5.
Previous research suggests that corticotropin-releasing hormone can act in the locus coeruleus to increase the firing of locus coeruleus neurons and elicit physiological responses resembling those associated with stress. The present study used immunocytochemical detection of Fos as a measure of neuronal activation to identify brain areas that were activated by bilateral injections of corticotropin-releasing hormone into the locus coeruleus of rats. Injection of corticotropin-releasing hormone into the locus coeruleus increased the expression of Fos in the locus coeruleus as compared with injection of vehicle into the locus coeruleus or injection of corticotropin-releasing hormone into neighbouring pontine sites. The pattern of Fos expression throughout the brain after injections of corticotropin-releasing hormone into the locus coeruleus was generally consistent with the anatomical organization of efferent projections arising from the locus coeruleus; increased Fos expression was observed in many brain areas including the ventral lateral septum, septohypothalamic nucleus, bed nucleus of the stria terminalis, the central amygdaloid nucleus, the dorsomedial nuclei of the hypothalamus, and the thalamic paraventricular and rhomboid nuclei. Foot shock also increased Fos expression in the locus coeruleus and the other brain regions that expressed Fos after corticotropin-releasing hormone injections into the locus coeruleus. A few brain regions, most notably the hypothalamic paraventricular nucleus, expressed Fos in response to foot shock but not corticotropin-releasing hormone. These results indicate that local injection of corticotropin-releasing hormone into the locus coeruleus stimulates the activity of the locus coeruleus neurons. However, the pattern of Fos expression throughout the brain evoked by injection of corticotropin-releasing hormone into the locus coeruleus does not fully replicate the effects of foot shock.
先前的研究表明，促肾上腺皮质激素释放激素可作用于蓝斑，增加蓝斑神经元的放电频率，并引发类似于与应激相关的生理反应。本研究采用免疫细胞化学检测Fos作为神经元激活的指标，以确定经双侧向大鼠蓝斑注射促肾上腺皮质激素释放激素后被激活的脑区。与向蓝斑注射赋形剂或向邻近脑桥部位注射促肾上腺皮质激素释放激素相比，向蓝斑注射促肾上腺皮质激素释放激素可增加蓝斑中Fos的表达。向蓝斑注射促肾上腺皮质激素释放激素后，全脑Fos表达模式总体上与源自蓝斑的传出投射的解剖结构一致；在许多脑区观察到Fos表达增加，包括腹外侧隔区、隔下丘脑核、终纹床核、中央杏仁核、下丘脑背内侧核以及丘脑室旁核和菱形核。足部电击也增加了蓝斑以及在向蓝斑注射促肾上腺皮质激素释放激素后表达Fos的其他脑区中的Fos表达。少数脑区，最显著的是下丘脑室旁核，对足部电击有Fos表达反应，但对促肾上腺皮质激素释放激素无反应。这些结果表明，向蓝斑局部注射促肾上腺皮质激素释放激素可刺激蓝斑神经元的活性。然而，向蓝斑注射促肾上腺皮质激素释放激素所诱发的全脑Fos表达模式并未完全复制足部电击的效应。
