Hypothalamic projections to locus coeruleus neurons in rat brain
Hypothalamic projections to locus coeruleus neurons in rat brain
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DOI：
10.1111/j.1460-9568.2005.04197.x
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发表时间：
2005-07-01
影响因子：
3.4
通讯作者：
Van Bockstaele, EJ
中科院分区：
文献类型：
--
作者：
Reyes, BAS;Valentino, RJ;Van Bockstaele, EJ
蓝斑（LC）神经元对自主神经和内脏刺激的反应与外周交感神经平行。本研究的特点是下丘脑传入与儿茶酚胺能神经元的突触组织在LC用电子显微镜。将室旁核（PVN）顺行标记的轴突终末的过氧化物酶标记与LC中酪氨酸羟化酶的金银标记相结合。大约19%的顺行标记的轴突终末形成突触专门与酪氨酸羟化酶免疫反应树突的LC。结合脑啡肽和促肾上腺皮质激素释放因子（CRF）的免疫细胞化学检测，从LC的逆行运输表明，大多数LC投射PVN神经元（30%）CRF免疫反应阳性，少数（2%）脑啡肽免疫反应阳性。最后，双逆行追踪从LC和正中隆起显示，PVN神经元的项目，LC是一个人口不同的投射到正中隆起。目前的数据表明，下丘脑神经元的人口是准备直接调节LC神经元的活动，并可能整合自主反应在大脑中通过影响LC神经元。此外，使用CRF作为神经激素的PVN神经元与使用CRF作为神经调质影响LC的PVN神经元不同。
Locus coeruleus (LC) neurons respond to autonomic and visceral stimuli and discharge in parallel with peripheral sympathetic nerves. The present study characterized the synaptic organization of hypothalamic afferents with catecholaminergic neurons in the LC using electron microscopy. Peroxidase labeling of axon terminals that were anterogradely labeled from the paraventricular nucleus (PVN) was combined with gold-silver labeling of tyrosine hydroxylase in the LC. Approximately 19% of the anterogradely labeled axon terminals formed synaptic specializations with tyrosine hydroxylase-immunoreactive dendrites in the LC. Retrograde transport from the LC combined with immunocytochemical detection of enkephalin and corticotropin-releasing factor (CRF) suggested that most of the LC-projecting PVN neurons (30%) were CRF immunoreactive and few (2%) were enkephalin immunoreactive. Finally, dual retrograde tracing from the LC and median eminence revealed that PVN neurons that project to the LC are a population distinct from that projecting to the median eminence. The present data suggest that a population of hypothalamic neurons is poised to directly modulate the activity of LC neurons and may integrate autonomic responses in brain by influencing LC neurons. Moreover, PVN neurons that use CRF as a neurohormone are distinct from those that use CRF as a neuromodulator to impact on the LC.