吗啡对大鼠心理依赖相关脑区超微结构和突触数量的影响

目的：观察不同时程吗啡依赖大鼠心理依赖相关脑区超微结构和突触数量的变化。方法：建立不同时程吗啡依赖大鼠模型,应用透射电镜对相关脑区皮质超微结构和突触进行观察计数。结果：吗啡依赖大鼠海马、杏仁核、豆状核和额叶皮质神经细胞线粒体肿胀、畸形,内质网扩张,多聚核糖体解聚,轴突、树突及突触数量增多;吗啡依赖4周组大鼠突触数量的增多与其他短时期或对照组大鼠相比,具有显著性差异;而8周组则具有高度显著性差异。结论：吗啡依赖大鼠心理依赖相关脑区神经细胞呈缺血缺氧性及退行性改变;突触数量增多,并随吗啡依赖时限的延长而更加明显。     

八肽胆囊收缩素在吗啡依赖及戒断大鼠相关脑区的表达变化

目的:探究慢性吗啡依赖及戒断大鼠相关脑区八肽胆囊收缩素(CCK-8)表达的变化。方法:利用Wistar大鼠建立慢性吗啡依赖及戒断模型,分为对照组(control)、吗啡依赖组(MOR)、纳洛酮催促戒断组(NAL)。Gellert-Holtzman评分评价吗啡成瘾及戒断程度,采用免疫组织化学和原位杂交技术分别检测相关脑区CCK-8蛋白及CCK mRNA表达的变化。结果:戒断组Gellert-Holtzman评分与对照组和吗啡依赖组比较显著增加;前额叶皮质(PFC)、黑质致密部(SNc)、中脑腹侧被盖区(VTA)CCK-8及CCK mRNA表达依赖组较对组明显升高,戒断后表达下降;杏仁核、蓝斑(LC)吗啡依赖后CCK-8及CCK mRNA表达较对照组显著增高,海马齿状回(PoDG)、杏仁核、LC戒断后较依赖组表达进一步升高;尾壳核(CPU)、伏隔核(NAc)、中脑导水管周围灰质(PAG)未检测到CCK-8及CCK mRNA的表达。结论:CCK-8参与了大鼠吗啡依赖与戒断过程并具有脑区特异性。     

八肽胆囊收缩素对吗啡戒断大鼠蓝斑和中脑导水管周围灰质CREB及p-CREB的影响

目的 探讨八肽胆囊收缩素（CCK-8）及其受体拮抗剂对吗啡戒断症状的影响及其相应的信号转导机制。方法 建立吗啡依赖及戒断动物模型,每组6只。应用改良柳田知司法对戒断症状评分,并采用免疫组织化学方法检测大鼠蓝斑和中脑导水管周围灰质内CREB及p-CREB的变化。结果 腹腔及侧脑室注射CCK-8,CCK1及CCK2受体拮抗剂均可明显降低戒断症状评分;吗啡依赖后蓝斑和中脑导水管内p-CREB明显增高,戒断后蓝斑内p-CREB水平较依赖组进一步增高,而中脑导水管内p-CREB却较依赖组下降。腹腔及侧脑室注射CCK-8,CCK1及CCK2受体拮抗剂均可逆转戒断后中脑导水管内p-CREB的降低;腹腔及侧脑室注射CCK1 及CCK2受体拮抗剂可逆转戒断后蓝斑内p-CREB的升高,而CCK-8却对蓝斑内p-CREB的表达无明显影响。结论 CCK-8可通过对蓝斑和中脑导水管内p-CREB的调节减轻吗啡戒断症状,且表现出明显的脑区特异性。     

大白鼠导水管周围灰质的传入性联系研究

应用辣根过氧化物酶微量及离子透入法注射在大白鼠的中脑导水管周围灰质的背侧区、外侧区、腹外侧区以及间脑与中脑交界处第Ⅲ脑室室周灰质部位。在导水管周围灰质的背侧区注射后,标记细胞可在:室旁核、下丘脑腹内侧核、下丘脑背内侧核、下丘脑后核、乳头体内侧核、暖昧带、导水管周围灰质腹外侧核和外侧核、上丘、下丘、中缝背核、第Ⅳ脑室室周灰质中出现。在导水管周围灰质的外侧区注射后,标记细胞则可在终纹床核、室旁核、下丘脑前核、下丘脑腹内侧核、丘脑内侧核、后联合巨细胞间质核、暖味带、导水管周围灰质腹外侧核、黑质网带、中缝背核、第Ⅲ及第Ⅳ脑室室周灰质中出现。在导水管周围灰质的腹外侧区注射后,始终可有标记的核群是。视上核、室旁核、第Ⅲ脑室室周灰质、导水管周围灰质外侧核、黑质网带、中缝背核、蓝斑。在间脑与中脑交界处第Ⅲ脑室室周灰质注射后,有标记的核群是:终纹床核、视上核、室旁核、下丘脑腹内侧核、丘脑内侧核、暖昧带、导水管周围灰质外侧核、黑质网带、中缝背核和蓝斑。     

吗啡依赖大鼠脊髓Ⅱ板层初级传入纤维突触性终末数量变化 …

目的 应用电镜定量方法探讨在吗啡依赖条件下,大鼠背根节感觉神经元发出的初级传入纤维能否在脊髓Ⅱ板层侧出支芽和建立新的突触。方法 用光镜体视学方法测知吗啡依赖组和对照组大鼠Ｌ４脊髓Ⅱ板层横切面积没有差异的情况下,直接比较了两组动物脊髓Ⅱ板层神经毡单位面积内突触性终末的数量变化。结果 吗啡依赖组脊髓Ⅱ板层来自初级传入纤维的突触性终末数,明显多于对照组的初级传入纤维突触性终末数,其终末数比对照组增多７０     

大鼠触液核中TRPC6的分布及其在吗啡依赖与戒断条件下的表达

目的:研究TRPC6在大鼠触液核(cerebrospinal fluid-contacting nucleus,CSF-CN)中的分布及其在吗啡依赖与戒断条件下的表达变化。方法:雄性SD大鼠随机分为4组:正常大鼠组、生理盐水组、吗啡依赖组和吗啡戒断组。每组大鼠进行戒断总评分(total withdrawal scores,TWS);采用侧脑室注射CB-HRP,并结合CB-HRPP/TRPC6免疫荧光双标技术,观察大鼠触液核内TRPC6的表达情况。结果:上述4组大鼠的戒断总评分分别为2.0±0.6、2.1±0.7、2.6±0.7和41.0±4.6,其中吗啡戒断组与其他三组相比,差异具有显著性(P<0.01);在侧脑室注射CB-HRP后,上述4组大鼠触液核内可观察到大量的CB-HRP标记神经元;同时在触液核内也可观察到部分神经元表达TRPC6免疫阳性。经计数,CB-HRP/TRPC6双标神经元的数量分别为81.78±4.93、79.44±7.09、254.61±15.36和260.00±12.04,其中吗啡依赖组和吗啡戒断组分别与其他两组相比,差异具有显著性(P<0.01);但吗啡依赖组和吗啡戒断组相比,差异无显著性(P>0.05)。结论:正常大鼠触液核内表达TRPC6;触液核可能通过上调TRPC6的表达参与吗啡依赖和戒断的形成。     

中脑导水管周围灰质、中缝背核、中缝大核和巨细胞网状核α部向孤束核的定位投射

本文用荧光金逆行追踪技术对大鼠下行抑制系统的中脑导水管周围灰质、中缝背核、中缝大核和巨细胞网状核a部向孤束核的投射进行了研究．将荧光金分别注入到孤束核的吻段、中段和尾段后，上述核团内出现的逆行标记神经元分布如下：（1）在冠状切面上，中脑导水管周围灰质内的荧光金标记细胞群集存在；在吻尾方向上呈柱状分布．三个实验组中，除吻段注射组的标记细胞数量少于其它2组外．在分布上完全一致。腹外侧区的标记细胞数量最多，但从尾侧到吻侧逐渐减少；背内侧区的标记细胞数量较少，以中、吻段较多；背外侧区的标记细胞出现于中脑导水管周围灰质的中、尾段，尾段最多，吻段内未见标记细胞．所有实验动物的中脑导水管周围灰质的内侧区均未出现标记细胞．（2）中缝背核内的标记细胞，多数位于其吻段的背侧都与收侧部的移行部，并且以注射区在孤束核的吻段者标记细胞较多；中缝背核的中尾段标记细胞量少，且散在于背外侧部，以注射区在孤束核的中段者标记细胞较多．（3）中缝大核内的标记细胞以核的尾段较多，吻段较少；巨细胞同状核a部内的标记细胞在吻尾方向上分布均匀。此两核团内的标记细胞数量以注射区在孤束核的中、尾段者较多。（4）上述脑区内标记细胞的数量均为注射区的同侧多于对侧。本研     

不同时程吗啡依赖对大鼠中脑腹侧被盖区多巴胺能神经元的影响

目的:观察不同时程吗啡依赖对大鼠中脑腹侧被盖区(ventral tegmental area,VTA)多巴胺能神经元的影响。方法:建立吗啡慢性依赖大鼠模型,石蜡包埋组织连续切片,免疫组织化学染色观察多巴胺能神经元特异性标记物酪氨酸羟化酶(tyrosine hydroxylase,TH)的表达变化。结果:TH免疫组化结果显示随着吗啡依赖时间的延长VTA区内TH阳性细胞逐渐减少,吗啡依赖6周组阳性细胞减少明显。结论:较长时程吗啡依赖大鼠VTA多巴胺能神经元损伤明显。     

吗啡依赖大鼠脊髓Ⅱ板层初级传入纤维突触性终末数量变化的电镜定量研究

目的　应用电镜定量方法探讨在吗啡依赖条件下 ,大鼠背根节感觉神经元发出的初级传入纤维能否在脊髓 板层侧支出芽和建立新的突触。　方法　用光镜体视学方法测知吗啡依赖组和对照组大鼠 L4脊髓 板层横切面积没有差异的情况下 ,直接比较了两组动物脊髓 板层神经毡单位面积内突触性终末的数量变化。　结果　吗啡依赖组脊髓 板层来自初级传入纤维的突触性终末数 ,明显多于对照组的初级传入纤维突触性终末数。其中来自无髓传入纤维的突触性终末数与对照组同类型的突触性终末数比较增加 6 1%。来自有髓传入纤维的突触性终末数比对照组增多 70 %。尤其是来自含有致密核芯小泡的初级传入纤维突触性终末数比对照组多 98%。　结论　吗啡可能促进初级传入纤维在脊髓 板层侧支出芽和建立新的突触     

慢性吗啡依赖和戒断对大鼠远位触液神经元环腺苷酸反应元件结合蛋白表达的影响

目的 研究慢性吗啡依赖和戒断大鼠远位触液神经元环腺苷酸反应元件结合蛋白(pCREB)表达的变化.方法 雄性SD大鼠24只,随机分为3组(n=8):空白对照组、慢性吗啡依赖组、慢性吗啡戒断组.采用侧脑室注射CB-HRP和CB-HRP/pCREB免疫组织化学双重标记技术,观察大鼠远位触液神经元pCREB表达的变化.结果 慢性吗啡依赖、戒断后,远位触液神经元出现CREB蛋白激活,两组CB-HRP/pCREB双标的神经元数量分别为223.0±61.5和213.0±50.6;与空白对照组相比较,磷酸化的CREB出现表达上调(P<0.01).吗啡依赖组和戒断组的CB.HRP双标神经元的数量相比,差异无显著性(P>0.05).结论 远位触液神经元通过上调磷酸化CREB的表达参与吗啡依赖和戒断的形成.     

Differential regulation of beta-arrestin 1 and beta-arrestin 2 gene expression in rat brain by morphine

Beta-arrestins are a family of regulatory and scaffold proteins functioning in signal transduction of G protein-coupled receptors including opioid receptors. Upon agonist stimulation, beta-arrestins bind to opioid receptors phosphorylated by G protein-coupled receptor kinases and promote receptor internalization and desensitization. Studies indicated that beta-arrestins are required in the development of morphine tolerance in mice. In the current study, we investigated the potential regulatory effects of morphine administration on beta-arrestin 1 and beta-arrestin 2 mRNA levels in different brain regions in rat using in situ hybridization method. Our results showed that the acute morphine administration (10 mg/kg) resulted in approximately 30% reduction in both beta-arrestin 1 and beta-arrestin 2 mRNA levels in hippocampus while the chronic morphine treatment (10 mg/kg, b.i.d., for 9 days) caused no significant change in level of either beta-arrestin mRNA. In locus coeruleus, both acute and chronic morphine treatments resulted in significant decreases (over 50%) in beta-arrestin 1 mRNA level but failed to induce any change in the level of beta-arrestin 2 gene expression. The acute morphine administration had no significant effect on beta-arrestin 1 or beta-arrestin 2 mRNA level in periaqueductal gray and cerebral cortex. However, after chronic morphine treatment, beta-arrestin 2 mRNA level decreased by 40% in periaqueductal gray and increased by 25% in cerebral cortex, in strong contrast to the unchanged beta-arrestin 1 mRNA level in these two brain regions. Furthermore, spontaneous or naloxone-precipitated withdrawal of morphine that did not affect the level of beta-arrestin 1 mRNA resulted in an aberrant increase (100% over control) in beta-arrestin 2 mRNA level in hippocampus. Our results thus demonstrated for the first time that opiate administration regulates level of beta-arrestin mRNAs in brain and the expression of beta-arrestin 1 and beta-arrestin 2 subtypes is differentially regulated in locus coeruleus, periaqueductal gray, and cerebral cortex by morphine. These data suggest that beta-arrestin 1 and beta-arrestin 2 may play different roles in the development of opioid tolerance and dependence.     

Regional Fos expression induced by morphine withdrawal in the 7‐day‐old rat

Human infants are often exposed to opiates chronically but the mechanisms by which opiates induce dependence in the infant are not well studied. In the adult the brain regions involved in the physical signs of opiate withdrawal include the periaqueductal gray area, the locus coeruleus, amygdala, ventral tegmental area, nucleus accumbens, hypothalamus, and spinal cord. Microinjection studies show that many of these brain regions are involved in opiate withdrawal in the infant rat. Our goal here was to determine if these regions become metabolically active during physical withdrawal from morphine in the infant rat as they do in the adult. Following chronic morphine or saline treatment, withdrawal was precipitated in 7‐day‐old pups with the opiate antagonist naltrexone. Cells positive for Fos‐like immunoreactivity were quantified within select brain regions. Increased Fos‐like labeled cells were found in the periaqueductal gray, nucleus accumbens, locus coeruleus, and spinal cord. These are consistent with other studies showing that the neural circuits underlying the physical signs of opiate withdrawal are similar in the infant and adult. © 2009 Wiley Periodicals, Inc. Dev Psychobiol 51: 544–552, 2009.     

Substance P in the cerebrospinal fluid-contacting nucleus contributes to morphine physical dependence in rats

The cerebrospinal fluid-contacting nucleus (CSF-CN), distributes and localizes in the ventral periaqueductal central gray (PAG) of the brainstem, which may influence actual composition of the cerebrospinal fluid (CSF) for non-synaptic signal transmission via releasing or absorbing bioactive substances. Many experiments have demonstrated that substance P (SP), a substance that is shown to be up-regulated in CSF-CN, plays an important role in the development of inflammatory pain and neuropathic pain. Thus in the present study, we hypothesize that SP in CSF-CN might contribute to morphine dependence in rats, inhibiting SP with (D-Pro2, D-Phe7, D-Trp9)-SP intracerebroventricular (i.c.v.) injection reduce chronic morphine dependence and withdrawal. Rats were repeatedly injected with morphine in five escalating doses for morphine physical dependence. Morphine withdrawal-like behavioral signs and morphine analgesia behaviors were monitored after naloxone administration following i.c.v. injection of (D-Pro2, D-Phe7, D-Trp9)-SP. And SP-expression of CSF-CN was evaluated with dual-label immunofluorescent technique on morphine withdrawal in rats. After i.c.v. treatment with (D-Pro2, D-Phe7, D-Trp9)-SP, the naloxone-precipitated withdrawal symptoms were significantly attenuated, paw withdrawal threshold/thermal withdrawal latency (PWT/TWL) were increased, and SP-expression in CSF-CN was significantly reduced than control group. SP, known a neurotransmitter/neuromodulator of nociception, has also been implicated in the signs of opioid withdrawal. This study provides the first evidence that SP in CSF-CN contributes to morphine physical dependence and withdrawal, which may provide an important and specific role in mediating the motivational aspects of opiates withdrawal via CSF - the parenchyma of the brain, and may represent a novel pharmacological route such as SP inhibitor i.c.v. injection for the control of drug abuse.     

Ethanol-induced effects on opioid peptides in adult male Wistar rats are dependent on early environmental factors

The vulnerability to develop alcoholism is dependent on both genetic and environmental factors. The neurobiological mechanisms underlying these factors are not fully understood but individual divergence in the endogenous opioid peptide system may contribute. We have previously reported that early-life experiences can affect endogenous opioids and also adult voluntary ethanol intake. In the present study, this line of research was continued and the effects of long-term voluntary ethanol drinking on the opioid system are described in animals reared in different environmental settings. Rat pups were subjected to 15 min (MS15) or 360 min (MS360) of daily maternal separation during postnatal days 1-21. At 10 weeks of age, male rats were exposed to voluntary ethanol drinking in a four-bottle paradigm with 5%, 10% and 20% ethanol solution in addition to water for 2 months. Age-matched controls received water during the same period. Immunoreactive (ir) Met-enkephalin-Arg6Phe7 (MEAP) and dynorphin B (DYNB) peptide levels were thereafter measured in the pituitary gland and several brain areas. In water-drinking animals, lower ir MEAP levels were observed in the MS360 rats in the hypothalamus, medial prefrontal cortex, striatum and the periaqueductal gray, whereas no differences were seen in ir DYNB levels. Long-term ethanol drinking induced lower ir MEAP levels in MS15 rats in the medial prefrontal cortex and the periaqueductal gray, whereas higher levels were detected in MS360 rats in the hypothalamus, striatum and the substantia nigra. Chronic voluntary drinking affected ir DYNB levels in the pituitary gland, hypothalamus and the substantia nigra, with minor differences between MS15 and MS360. In conclusion, manipulation of the early environment caused changes in the opioid system and a subsequent altered response to ethanol. The altered sensitivity of the opioid peptides to ethanol may contribute to the previously reported differences in ethanol intake between MS15 and MS360 rats.     

吗啡依赖性大鼠海马CA1区NKB细胞的改变

目的观察吗啡依赖性大鼠海马CA1区NKB细胞的变化.方法用皮下注射吗啡法建立雄性大鼠吗啡依赖模型.用免疫组织化学和图像分析方法观察大鼠CA1区NKB细胞的变化.结果吗啡依赖性大鼠海马CA1区NKB细胞免疫反应减弱,与对照组相比差异显著(P＜0.01).结论NKB细胞减少与吗啡依赖性的发生、发展有关.     

Efferent projections of the periaqueductal gray in the rabbit.

The efferent projections of the periaqueductal gray in the rabbit have been described by anterograde tract-tracing techniques following deposits of tritiated leucine, or horseradish peroxidase, into circumscribed sites within dorsal, lateral or ventral periaqueductal gray. No attempts were made to place labels in the fourth, extremely narrow (medial), region immediately surrounding the aqueduct whose size and disposition did not lend itself to confined placements of label within it. These anatomically distinct regions, defined in Nissl-stained sections, corresponded to the same regions into which deposits of horseradish peroxidase were made in order for us to describe afferent projections to the periaqueductal gray. In this present study distinct ascending and descending fibre projections were found throughout the brain. Terminal labelling was detected in more than 80 sites, depending somewhat upon which of the three regions of the periaqueductal gray received the deposit. Therefore, differential projections with respect to both afferent and efferent connections of these three regions of the periaqueductal gray have now been established. Ventral deposits disclosed a more impressive system of ramifying, efferent fibres than did dorsal or lateral placements of labels. With ventral deposits, ascending fibres were found to follow two major pathways from periaqueductal gray. The periventricular bundle bifurcates at the level of the posterior commissure to form hypothalamic and thalamic components which distribute to the anterior pretectal region, lateral habenulae, and nuclei of the posterior commissure, the majority of the intralaminar and midline thalamic nuclei, and to almost all of the hypothalamus. The other major ascending pathway from the periaqueductal gray takes a ventrolateral course from the deposit site through the reticular formation or, alternatively, through the deep and middle layers of the superior colliculus, to accumulate just medial to the medial geniculate body. This contingent of fibres travels more rostrally above the cerebral peduncle, distributing terminals to the substantia nigra, ventral tegmental area and parabigeminal nucleus before fanning out and turning rostrally to contribute terminals to ventral thalamus, subthalamus and zona incerta, then continuing on to supply amygdala, substantia innominata, lateral preoptic nucleus, the diagonal band of Broca and the lateral septal nucleus. Caudally directed fibres were also observed to follow two major routes. They either leave the periaqueductal gray dorsally and pass through the gray matter in the floor of the fourth ventricle towards the abducens nucleus and ventral medulla, or are directed ventrally after passing through either the inferior colliculus or parabrachial nucleus. These ventrally directed fibres merge just dorsal to the pons on the ventral surface of the brain.(ABSTRACT TRUNCATED AT 400 WORDS)     

Isolated catecholaminergic projections from substantia nigra and locus coeruleus to caudate,hippocampus and cerebral cortex formed by intraocular sequential double brain grafts

Summary Sequential intraocular grafting of defined areas from fetal rat brain to adult host rats was used to explore the possibility that such double grafts would become interconnected. Norepinephrine- containing neurons of the locus coeruleus were grafted together with either parietal cerebral cortex, hippocampus, or the caudate nucleus. Dopamine-containing neurons of the substantia nigra were transplanted together with either parietal cerebral cortex or the caudate nucleus. The brainstem grafts showed good survival and development in oculo, using both histochemical and electrophysiological criteria. Locus coeruleus neurons were found to innervate cerebral cortex, hippocampus, and the caudate nucleus. Substantia nigra neurons invaded cerebral cortex abundantly, with a terminal distribution typical of cortical DA terminals in situ. The innervation of the caudate nucleus from substantia nigra transplants was variable, but areas of dense confluent terminals were observed.We conclude that sequential brain grafting in oculo permits generation of isolated yet defined catecholaminergic projections, which are suitable for electrophysiological, pharmacological, and histochemical studies.     

用激光扫描共聚焦显微镜观察吗啡成瘾对大鼠海马锥体神经细胞内DNA、RNA的影响

为了取得吗啡成瘾对神经细胞内核酸代谢以及神经系统发育影响的直接证据 ,藉以探索吗啡成瘾的神经生物学机制及对吗啡成瘾的治疗途径。本研究根据新型荧光探针 Acridine orange(AO)能与活细胞内 DNA和 RNA特异性结合后发出荧光的特性 ,利用激光共聚焦显微镜对吗啡成瘾新生大鼠的海马神经细胞 (主要是锥体细胞 )内 DNA和 RNA的荧光像素进行观察 ,并用图象分析技术进行处理 ,了解分析吗啡成瘾对神经细胞形态变化、细胞内 DNA、RNA代谢的影响。结果表明 :吗啡成瘾组大鼠神经细胞 DNA和 RNA的荧光像素之比平均为 0 .4 96 7± 0 .2 342 ,而对照组大鼠神经细胞的 DNA与 RNA的荧光染色像素之比为 17.9396± 6 .6 547。说明吗啡成瘾大鼠神经细胞内 RNA明显增多 ,而 DNA却明显低于对照组 ,差异显著 (P<0 .0 1) ;与正常对照组相比 ,吗啡成瘾大鼠海马锥体细胞体积明显增大 ,RNA荧光强度明显增强 ,而 DNA荧光强度明显降低。提示 :(1)吗啡成瘾能明显抑制大鼠海马锥体细胞的 DNA合成 ,刺激 RNA合成 ,促使神经细胞不成熟分化和体积增大 ;(2 )吗啡成瘾所致的神经细胞内 [Ca2 + ]i增高与神经细胞的成熟分化异常有着某种内在联系     

Immunohistochemical mapping of neurophysins and calcitonin gene-related peptide in the human brainstem and cervical spinal cord

Our study investigates the distribution of neurophysins (Nph), proteins that are part of the precursors for vasopressin and oxytocin, and calcitonin gene-related peptide (CGRP) in the human brainstem by immunohistochemistry. Both peptides were found in discrete regions of the human hindbrain. Nph could be demonstrated exclusively in fibers and punctate perineural varicosities that were travelling within the mesencephalic central gray, substantia nigra, as well as locus coeruleus, medial longitudinal fascicle, raphe, nucleus of the solitary tract, lateral reticular nucleus and area postrema. A few varicosities were seen in the substantia gelatinosa of the spinal trigeminal tract and its continuation into the dorsal horn of the cervical spinal cord. In contrast to these observations. CGRP-immunoreactive fibers were found to be densest in the spinal tract of the trigeminal nerve and the dorsal horn of the spinal cord. In addition, fibers and varicosities could be demonstrated in numerous distinct brain regions, such as locus coeruleus and subcoeruleus, solitary tract, cuneate nucleus, raphe and periaqueductal gray. CGRP-immunoreactivity was also present in perikarya in the ventral horn of the spinal cord, as well as motor nuclei of cranial nerves, i.e., hypoglossal nucleus, ambiguous nucleus. Our results suggest that Nph-immunoreactivity in the human brainstem may be present predominantly within long fiber projections from hypothalamic neurosecretory nuclei, in analogy to data obtained from rodents, whereas CGRP may play a role in the branchiomotor system as well as in intrinsic or extrinsic projections involved in autonomic regulation and integration of sensory information.