大鼠三叉神经脊束核尾侧亚核和脊髓向丘脑和臂旁核的谷氨酸能投射

本研究用荧光金逆行追踪与免疫荧光组比技术相结合的方法,对大鼠三叉神经脊束核尾侧亚核和脊髓向丘脑和臂旁核的谷氨酸能投射进行了观察。磷酸激活的谷氨酸胺酶（PAG）是谷氨酸能神经元的特异性标识物。PAG样阳性胞体主要位于三叉神经脊束核尾侧亚核和颈髓背角的Ⅰ层,少量PAG样阳性胞体也见于它们的Ⅱ层外侧部及外侧网状核。将荧光金注入丘脑腹基底复合体后．荧光金逆标神经元主要见于对侧三叉神经脊束核尾侧亚核和颈髓背角的Ⅰ层及外侧网状核;将荧光金注入臂旁核后,荧光金逆标神经元也主要见于对侧三叉神经脊束核尾侧亚核和颈髓背角的Ⅰ层及外侧网状核。三叉神经脊束核尾侧亚核向丘脑腹基底复合体投射神经元的12．4％,向臂旁核投射神经元的13．2％呈PAG样阳性;颈髓背角浅层向丘脑瓜基底复合体投射神经元的12．7％,向臂旁核投射神经元的14．3％呈PAG样阳性。向丘脑腹基底复合体和臂旁核投射的PAG／荧光金双标神经元分别占三叉神经脊束核尾侧亚核浅层内PAG样阳性神经元总数的13％和24．6％,向丘脑腹基底复合体和臂旁核投射的PAG／荧光金双标神经元分别占颈髓背角浅层内PAG样阳性神经元总数的11．6％和30．1％。外侧网状核内的部分PAG样阳性神经元也向丘脑腹基底复合体或臂旁核投射。Ⅰ层内的双?     

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     

大鼠臂旁核内5-羟色胺阳性纤维和终末的来源

本研究采用荧光金(FG)逆行追踪与5-羟色胺(5-HT)免疫荧光组化染色相结合的双重技术观察了臂旁核(PBN)内5-HT阳性神经纤维和终末的来源。将FG注入PBN后,FG逆标神经元主要分布在三叉神经核簇、脑干网状结构外侧小细胞部、中缝核簇和中脑导水管周围灰质(PAG);免疫荧光组化染色的结果显示5-HT阳性神经元主要位于中缝核簇和PAG;在中缝核簇和PAG内可见FG逆标并呈5-HT阳性的双重标记神经元。上述结果表明,中缝核簇和PAG内的5-HT能神经元向PBN发出投射,它们在躯体和内脏感觉信息的传递和调控方面发挥重要作用。     

大鼠孤束核内儿茶酚胺能神经元接受面口部深层组织伤害性信息并向臂旁核投射的形态学研究

为了探讨孤束核(NTS)内儿茶酚胺能神经元是否与面口部深层组织的伤害性信息有关并向臂旁核投射,本研究运用荧光金(FG))逆行追踪,福尔马林刺激咬肌和免疫荧光技术相结合的三重标记方法,在荧光显微镜下观察了大鼠NTS内酪氨酸羟化酶(TH)阳性并表达FOS蛋白的神经元向臂旁核的投射。将2％FG注入一侧臂旁外侧核后,向同侧咬肌内注射2％福尔马林溶液,并行TH和FOS免疫荧光组织化学染色,荧光显微镜下在同侧NTS内的连合、内侧、中间内侧和腹侧亚核中可见重叠分布的FG、FOS、TH单标神经元以及FG／TH、FOS／TH、FOS／FG双标和FG／FOS／TH三标神经元。FG／TH和FOS／TH双标神经元分别占同侧NTS内TH阳性神经元总数的28.6％和34.8％;FOS／FG双标神经元占同侧FG逆标神经元总数的26.4％;FG／FOS／TH三标神经元分别占同侧TH阳性神经元和FG逆标神经元总数的23.7％和8.4％。本结果提示大鼠NTS中的部分儿茶酚胺能神经元接受面口部深层组织的伤害性信息并向臂旁外侧核传递。     

大鼠三叉神经脊束间质核内接受面口部躯体伤害性信息的calbindinD-28k神经元向孤束核的投射

为探讨三叉神经脊束间质核内的 calbindin D-2 8k神经元是否接受并传递面口部躯体伤害性信息到孤束核 ,本研究应用荧光金逆行束路追踪结合 FOS和 calbindin D-2 8k免疫荧光组织化学技术 ,观察了三叉神经脊束间质核的 calbindin D-2 8k和FOS双重免疫反应阳性的神经元向孤束核的投射。向右侧孤束核内注射荧光金并向右侧上、下唇皮下注射福尔马林 ,发现荧光金逆标细胞和 FOS免疫反应阳性细胞主要分布于注射侧的三叉神经脊束间质核的背侧边缘旁核和三叉旁核 ;大量的 calbindinD-2 8k免疫阳性细胞分布于双侧三叉神经脊束间质核内。此处的大部分荧光金逆标细胞 (约 74.4% )呈 calbindin D-2 8k免疫反应阳性。在此二者的双重阳性细胞中 ,又有一部分 (约 41.0 % )为同时呈 FOS免疫反应阳性的三重阳性神经元。结果提示 ,三叉神经脊束间质核内接受面口部躯体伤害性信息的 calbindin D-2 8k神经元可直接投射至孤束核 ,calbindin D-2 8k神经元可能在躯体伤害性信息经三叉神经脊束间质核向孤束核的传递过程中发挥重要作用     

大鼠臂旁核内nNOS阳性传入纤维的脑内来源

目的探讨大鼠臂旁核(PBN)内神经元型一氧化氮合酶(nNOS)阳性传入纤维的脑内来源。方法在大鼠PBN内微量注射荧光金(FG),结合nNOS免疫荧光双标技术,观察FG/nNOS双标神经元在脑内的分布情况。结果FG/nNOS双标神经元主要分布在孤束核(NST)、延髓嘴侧腹外侧区(RVL)、中缝背核(DR)、导水管周围灰质(PAG)和下丘脑室旁核(PVN)。结论NST、RVL、DR、PAG和PVN内的nNOS阳性投射神经元是PBN内nNOS阳性纤维终末的主要来源。     

大鼠三叉神经脊束间质核内接受内脏伤害性信息的含CB神经元向孤束核的投射

目的 探讨大鼠三叉神经脊束间质核(INV)内接受内脏伤害性信息的含calbindin D-28K(CB)神经元与孤束核(NTS)的投射联系。方法 用福尔马林刺激上消化道，应用荧光金(FG)逆行束路追踪结合Fos和CB的免疫荧光组织化学三重标记法。结果 INV的背侧边缘旁核(PaMd)和三叉旁核(PaV)内可见到大量FG逆标细胞，以注射FG的同侧为主。大部分FG逆标细胞(约71.2％)为CB免疫反应阳性。部分FG和CB双标记神经元(约31．5％)同时呈Fos免疫反应阳性的三重标记。结论 INV内部分接受内脏伤害性刺激的CB神经元可直接投射至NTS，含CB的神经元在内脏伤害性信息经INV向NTS的传导通路中，可能发挥重要作用.     

大鼠三叉神经脊束核尾侧亚核和脊髓向丘脑和臂旁核的强啡肽能和一氧化氮能投射

本文用荧光金逆行追踪与免疫荧光组化染色相结合的方法，对大鼠三叉神经脊束核尾侧亚核和颈髓背角浅层向丘脑腹基底复合体和臂旁核的强啡肽能和NO能投射进行了研究．强啡肽原前体样阳性胞体主要位于尾侧亚核和颈髓背角的Ⅰ层和Ⅱ层外侧部；NOS样阳性胞体主要位于尾侧亚核和颈够背角Ⅱ层，Ⅰ层较少。将荧光金注入丘脑腹基底复合体后，荧光金逆标神经元主要见于对侧尾侧亚核、颈髓背角的Ⅰ层和外侧网状核，Ⅱ层偶见；将荧光金注入臂旁核后，逆标神经元主要见于同侧尾侧亚核和颈髓背角的Ⅰ、Ⅱ层，少量位于外侧网状核。尾侧亚核向丘脑瓜基底复合体投射神经元的16．6％，向臂旁核投射神经元的24．8％呈强啡肽原前体样阳性；颈髓背角浅层向丘脑腹基底复合体投射神经元的19．2％，向臂旁核投射神经元的272％呈强啡肽原前体样阳性。向丘脑腹基底复合体和臂旁核投射的强啡肽原前体／荧光金双标神经元分别占尾侧亚核浅层内强啡肽原前体样阳性神经元总数的7％和18％，分别占颈髓背角浅层内强啡肽原前体样阳性神经元总数的8．1％和21．9％。这些双标神经元多呈大梭形及中等大圆形和梨形。由昆侧亚核向丘脑腹基底复合体投射神经元的5．1％呈NOS阳性，向臂旁核投射神经元的11．8％呈NOS阳性。由颈髓背角浅层向丘脑版?     

Collateral Projections from the Lateral Parabrachial Nucleus to the Central Amygdaloid Nucleus and the Ventral Tegmental Area in the Rat

Lateral parabrachial nucleus (LPB) is a critical region in the integration and transmission of peripheral nociceptive information. The parabrachio-amygdaloid (P-Amy) pathway and parabrachio-ventral tegmental area (P-VTA) pathway is thought to be significant in regulation of pain-related negative emotions. In present study, retrograde tract tracers Fluoro-gold (FG) and tetramethylrhodramine-dextran (TMR) were stereotaxically injected into the right central amygdaloid nucleus (CeA) and right VTA, respectively. Then, part of these rats were performed with the spare nerve injury (SNI) in the controlateral side of FG and TMR injection. Afterwards, double- or triple-immunofluorescent histochemistry was used to examine FG/TMR double- and FG/TMR/FOS or FG/TMR/CGRP triple-labeled neurons in the LPB. The results showed that all of FG, TMR single- and FG/TMR double-labeled neurons were distributed in the LPB bilaterally with an ipsilateral predominance. The proportion of FG/TMR double-labeled neurons to the total number of FG- and TMR-labeled neurons was 10.78% and 13.07%, respectively. Nearly all of the FG/TMR double-labeled neurons (92.67%) showed calcitonin gene-related peptide (CGRP) immunopositive. On the other hand, in the SNI rats, about 89.49% and 77.87% of FG- and TMR-labeled neurons were FG/FOS- and TMR/FOS-positive neurons; about 93.33% of the FG/TMR double-labeled neurons were FOS-LI. Our results suggest that the part of CGRP immunopositive neurons in the LPB send projection fibers to both the CeA and VTA by the way of axon collaterals, which are activated by the nociceptive stimulation in the SNI condition, and may play an important role in the transmission of peripheral nociceptive information. Anat Rec, 302:1178–1186, 2019. © 2018 The Authors. The Anatomical Record published by Wiley Periodicals, Inc. on behalf of American Association of Anatomists.     

大鼠延髓至下丘脑室旁核的儿茶酚胺能投射神经元在胃伤害性刺激后的FOS表达

用ＨＲＰ注入下丘脑室旁核逆行追踪与抗Ｆｏｓ和抗酪氨酸羟化酶（ＴＨ）双重免疫细胞化学相结合的三重标记方法，对大鼠孤束核和延髓腹外侧区至下丘脑室旁核的儿茶酚胺能投射神经元对胃伤害性刺激后的ｃ－ｆｏｓ表达进行了观察，发现孤束核和延髓腹外侧区有７种不同的标记细胞：ＨＲＰ、Ｆｏｓ、ＴＨ单标细胞，Ｆｏｓ／ＨＲＰ、Ｆｏｓ／ＴＨ、ＨＲＰ／ＴＨ双标细胞，Ｆｏｓ／ＨＲＰ／ＴＨ三标细胞。上述７种标记细胞主要分布在延髓中、尾段孤束核的内侧亚核、连合亚核和延髓腹外侧区以及两者之间的网状结构。ＨＲＰ标记细胞以注射侧为主，对侧有少量分布。本文结果证明，大鼠孤束核和延髓腹外侧区至下丘脑室旁核投射的部分儿茶酚胺能神经元可能参与胃伤害性刺激的传导和调控。     

Somatic noxious mechanical stimulation induces Fos expression in the postsynaptic dorsal column neurons in laminae III and IV of the rat spinal dorsal horn

This study was conducted to ascertain the possible expression of Fos-like immunoreactivity (Fos-LI) in the postsynaptic dorsal column (PSDC) neurons in response to noxious mechanical stimulation of the forepaw glabrous area of normal rats. For this purpose, Fos immunohistochemistry along with Fluoro-Gold (FG) retrograde tracing was utilized. After repeated noxious pinching of the forepaw glabrous area, there was a marked increase in number of Fos-LI neurons in the dorsal horn, including Rexed's laminae III and IV, at C5-T1 spinal cord segments ipsilateral to the stimulation. Between segments C5 and T1, about 40% of the Fos-LI neurons in laminae III and IV were distributed at segment C7. In the rats subjected to the noxious pinch coupled with FG injection into the right cuneate nucleus, PSDC neurons double labeled with Fos and FG were localized in the ipsilateral laminae III and IV extending from segment C5 to T1, with about 70% of them distributed at segments C6 and C7. At segment C6 or C7, double-labeled neurons made up about 10% of the PSDC neurons that projected their axons to the cuneate nucleus. Most of the double-labeled neurons appeared fusiform with their primary dendrites projected dorso-ventrally. The present results suggest that the morphologically distinct, subclasses of PSDC neurons in spinal laminae III and IV may contribute to the central transmission of mechanical nociceptive information through the dorsal column into the cuneate nucleus.     

Estradiol-17β-responsive A1 and A2 noradrenergic cells of the brain stem project to the bed nucleus of the stria terminalis in the ewe brain: A possible route for regulation of gonadotropin releasing hormone cells

We have studied brain stem cells in the ewe brain that project to the bed nucleus of the stria terminalis (BNST) and determined if these cells are activated by estradiol-17β. This would predicate an indirect role in the estradiol-17β regulation of gonadotropin releasing hormone (GnRH) cells, since these receive input from the BNST. Ovariectomized ewes received 50 μg estradiol-17β benzoate (i.m.) 1 h prior to brain collection, so that activated cells could be identified by Fos immunohistochemistry. Retrograde tracer (FluoroGold; FG), was injected into the three divisions of the BNST and labeled cells were mapped to the A1 and A2 regions and the parabrachial nucleus (PBN) of the brain stem. With FG injection into the dorsal and lateral BNST, all FG-containing cells in the caudal A1 and 45% of those in A2 stained for dopamine-β-hydroxylase (DBH), indicating noradrenergic type. No FG-labelled cells in the PBN were DBH-positive. In A1 and A2 respectively, 42% and 46% of FG-labelled cells were Fos-positive, with no double-labeling in cells of the PBN. In ewes receiving FG injections into the ventral BNST, estrogen receptor (ER)α-immunoreactive nuclei were found in 82% of A1-FG labeled and 38% of A2-FG labeled cells. No FG-labelled cells of the PBN were ERα-positive. Anterograde tracing from A1 with microruby injection identified projections to the PBN, BNST and preoptic area (POA). Thus, A1 and A2 noradrenergic neurons project to the BNST in the ewe brain, express ERα and are activated by estradiol-17β. These noradrenergic, estrogen-responsive cells may provide indirect input to GnRH cells, via the BNST.     

Cells of origin of vagal motor neurons projecting to different parts of the stomach in the rat: confocal laser scanning and electron microscopic study

Parasympathetic motor neurons in the dorsal motor nucleus of the vagus (DMV) innervate the stomach by way of the gastric and hepatic branches of the vagus nerve. To investigate whether single neurons of the DMV provide collateral innervations to various parts of the stomach, we injected the retrograde tracer Fluoro-Gold (FG) into the cardia and the retrograde tracer cholera toxin subunit b (CTb) into the antrum or the pylorus of the same animal. Both retrogradely FG-labeled and CTb-labeled neurons were found throughout the DMV. Almost all CTb-labeled neurons (97%) were double-labeled with FG after injection of FG into the cardia and CTb into the antrum, while only a few CTb-labeled neurons (11%) were double-labeled with FG after injection of FG into the cardia and CTb into the pylorus. Thus, the cardia and the antrum received collateral projections, but the pylorus received projections mainly from different neurons in the DMV. These results indicate that different neurons in the DMV activate either the cardia or the pyloric sphincter muscles. We also labeled, retrogradely, the neurons projecting to the cardia and the pylorus in the DMV with cholera toxin-conjugated horseradish peroxidase (CT-HRP) to examine their ultrastructural characteristics. Although the neurons projecting to the cardia (21.6×15.0 µm, 248.0 µm² per section) were significantly smaller than the neurons projecting to the pylorus (27.5×15.9 µm, 323.2 µm² per section), their ultrastructural appearances were similar. Both types of neurons were small-to-medium sized, round or oval in shape, and generally had a small amount of cytoplasm containing a few Nissl bodies and a round nucleus. The average number of axosomatic terminals per section was low in the neurons projecting to the cardia (2.3) and the neurons projecting to the pylorus (3.0). Almost all axon terminals contacting these motor neurons contained round synaptic vesicles and made asymmetric synaptic contacts (Grays type I).     

Parvalbumin样阳性神经元大鼠三叉神经本体觉中枢通路上的分布--FG逆标与免疫组化相结合研究

已往研究证明：三叉神经吻侧亚核背内侧部及其邻接的网状结构（Ｖｏｄｍ－ＬＲＦ）和由三叉上核尾外侧部（Ｖｓｕｐ－ＣＬ）、三叉神经感觉主核背内侧部（Ｖｐｄｍ）以及ＡＶＭ和ＡＤＯ等两个小核团所构成的“带状区”分别为三叉神经领域本体觉中枢通路的第二、三级神经元所在地。Ｐａｒｖａｌｂｕｍｉｎ（ＰＶ）是常见的钙结合蛋白。在该通路的Ｖｏｄｍ－ＬＲＦ和“带状区”内存在许多ＰＶ样阳性细胞。但这些ＰＶ样阳性神经元究系属     

Topographical distributions of endomorphinergic pathways from nucleus tractus solitarii to periaqueductal gray in the rat

In the central nervous system (CNS), endomorphin 1 (EM1)- and endomorphin 2 (EM2)-containing neuronal cell bodies have been found in the nucleus tractus sollitarii (NTS) and the hypothalamus, and EMergic fibers and terminals are distributed widely in many regions of the CNS, including the periaqueductal gray (PAG). The aim of the present study was to examine whether EM-expressing neurons in the NTS of the rat send their axons to the PAG, and determine whether the EMergic pathway from the NTS to the PAG is topographic by using. Immunofluorescent staining for EM1 or EM2 combined with retrograde and anterograde tract-tracing methods. The results showed that after injecting tetramethyl rhodamine dextran-amine (TMR) into the ventrolateral or lateral column of the PAG, some EM1- or EM2-immunoreactive (IR) neurons in the NTS were retrogradely labeled with TMR, and the majority of the EM-IR/TMR double-labeled neurons were mainly distributed in the medial and commissural subnuclei of the NTS. Following injection of biotinylated dextran amine (BDA) into the medial or commissural subnucleus of the NTS, EM1-IR/BDA and EM2-IR/BDA double-labeled fibers and terminals were mainly distributed in the ventrolateral or lateral column of the PAG, respectively. The results indicate that EMergic pathway from the NTS to PAG is topographically organized, and suggest that EMs released from NTS to PAG projecting terminals may bind to μ-opioid receptor on the PAG neurons, and thereby contribute to various functions.     

孤束核内儿茶酚胺能神经元汇聚内脏传入与口面部躯体伤害性信息并向臂旁核投射

为了研究内脏初级传入与口面部深层组织躯体伤害性信息是否汇聚于孤束核(NTS)中向臂旁核(PBN)投射的儿茶酚胺(CA)能神经元。本实验将SD大鼠随机分为两组。第一组动物以生物素化的葡聚糖胺(BDA)注入颈部迷走神经主干跨节追踪,四甲基罗达明(TMR)注入臂旁外侧核(LPB)逆行追踪,福尔马林刺激咬肌并行FOS的免疫荧光组织化学染色;第二组动物以BDA注入颈部迷走神经主干跨节追踪,福尔马林刺激咬肌并行FOS和酪氨酸羟化酶(TH)染色。在激光扫描共聚焦显微镜下对两组大鼠NTS内的标记细胞和纤维进行了观察。两组实验中,主要在NTS的内侧、中间内侧和连合亚核内观察到重叠分布的TMR、FOS或TH、FOS单标神经元。其中部分TMR逆行标记的或TH阳性神经元呈FOS阳性并与BDA跨节标记的纤维和终末形成紧密接触。提示大鼠NTS内的CA能神经元可能汇聚了内脏初级传入和口面部深层组织的躯体伤害性刺激信息并向LPB投射。     

Responses of hypothalamic neurons to stimulation of the vestibular nerve and lateral vestibular nucleus in the rabbit

Acute experiments were performed on rabbits to study the responses of neurons in the anterior, ventromedial, and posterior nuclei of the hypothalamus to single, paired, and rhythmic stimulation of the vestibular nerve and lateral vestibular nucleus of Deiters. The data obtained showed that neurons of the posterior nucleus of the hypothalamus were the most sensitive. Three types of response were seen from hypothalamic neurons, with short, long, and intermediate latent periods. This provides evidence that ascending afferent spike activity from the lateral vestibular nucleus of Deiters to the hypothalamus is mediated by mono-, oligo-, and polysynaptic pathways. Translated from Rossiiskii Fiziologicheskii Zhurnal imeni I. M. Sechenova, Vol. 83, No. 11-12, pp. 49–56, November–December, 1997.     

大鼠腰骼髓“内脏面”传出和上行投射神经元的定位分布——HRP与荧光金追踪法研究

用HRP与荧光金(FG)结合的示踪法,观察了大鼠腰骶髓“内脏面”副交感节前神经元和上行投射神经元的定位分布。发现FG注入一侧臂旁外侧核或Barrington核后,逆行标记的金色荧光细胞出现于双侧L_5～S_2的“内脏面”,细胞密集于后连合核和中间带外侧核(IML),此外,还出现于双侧的I层及外侧脊髓核(LSN)。HRP注射于一侧盆神经后,逆标细胞出现于术侧的L_6和S的IML,偶见于中介核(IC)。在IML内,HRP标记的副交感节前神经元位于其腹侧份,而FG标记的上行投射神经元主要位于背侧和背内侧部,亦可见少数FG标记细胞混杂在HRP标记细胞之间。本研究结合已有的研究对IML的命名、组成和功能以及LSN的组成进行了讨论。     

杏仁核参与大鼠哮喘发作及其机制探讨

为探讨杏仁核是否参与大鼠哮喘发作及其机制,采用卵蛋白致敏哮喘大鼠模型,运用WGA-HRP逆行追踪与免疫组织化学染色相结合的双重标记方法,在光镜下观察向下丘脑室旁核(PVN)发出投射的杏仁核神经元内Fos蛋白的表达情况。结果显示:杏仁核内可观察到三种阳性细胞,即HRP逆标神经元、Fos阳性神经元和HRP/Fos双标神经元。Fos阳性细胞呈双侧分布,主要分布在杏仁核的内侧亚核(MeA)和中央亚核(CeA);HRP逆标神经元和HRP/Fos双标神经元分布在注射区同侧的内侧杏仁核,内侧杏仁核内HRP/Fos双标神经元占HRP单标神经元的33.55%。本研究结果提示,哮喘大鼠发作时,杏仁核、下丘脑室旁核的神经元兴奋,且杏仁核到下丘脑室旁核的直接投射可能参与了哮喘发作的调控。     

Nystagmus induced by electrical stimulation of the vestibular and prepositus hypoglossi nuclei in the monkey: evidence for site of induction of velocity storage

Summary Electrical stimulation of the vestibular nuclei (VN) and prepositus hypoglossi nuclei (PPH) of alert cynomolgus monkeys evoked nystagmus and eye deviation while they were in darkness. At some sites in VN, nystagmus and after-nystagmus were induced with characteristics suggesting that velocity storage had been excited. We analyzed these responses and compared them to the slow component of optokinetic nystagmus (OKN) and to optokinetic after-nystagmus (OKAN). We then recorded unit activity in VN and determined which types of nystagmus would be evoked from the sites of recording. Nystagmus and eye deviations were also elicited by electrical stimulation of PPH, and we characterized the responses where unit activity was recorded in PPH. Horizontal slow phase velocity of the VN storage responses was contralateral to the side of stimulation. The rising time constants and peak steady-state velocities were similar to those of OKN, and the falling time constants of the after-nystagmus and of OKAN were approximately equal. Both the induced after-nystagmus and OKAN were habituated by stimulation of the VN. When horizontal after-nystagmus was evoked with animals on their sides, it developed yaw and pitch components that tended to shift the vector of the slow phase velocity toward the spatial vertical. Similar cross-coupling occurs for horizontal OKAN or for vestibular post-rotatory nystagmus elicited in tilted positions. Thus, the storage component of nystagmus induced by VN stimulation had the same characteristics as the slow component of OKN and the VOR. Positive stimulus sites for inducing nystagmus with typical storage components were located in rostral portions of VN. They lay in caudal ventral superior vestibular nucleus (SVN), dorsal portions of central medial vestibular nucleus (MVN) caudal to the abducens nuclei and in adjacent lateral vestibular nucleus (LVN). More complex stimulus responses, but with contralateral after-nystagmus, were induced from surrounding regions of ventral MVN and LVN, rostral descending vestibular nucleus and the marginal zone between MVN and PPH. Vestibular-only (VO), vestibular plus saccade (VPS) and tonic vestibular pause (TVP) units were identified by extracellular recording. Stimulation near type I lateral and vertical canalrelated VO units elicited typical storage responses with after-nystagmus in 23 of 29 tracks (79%). Stimulus responses were more complex from the region of neurons with oculomotor-related signals, i.e., TVP or VPS cells, although after-nystagmus was also elicited from these sites. Effects of vestibular nerve and nucleus stimulation were compared. Nerve stimulation evoked nystagmus with both a rapid and slow component and after-nystagmus. There was a more prominent rapid rise in slow phase velocity, higher peak velocities, shorter latencies and a shorter falling time constant from nerve than from nucleus stimulation. This indicates more prominent activation of rapid pathways from nerve stimulation. From a comparison of nerve- and nucleus-induced nystagmus, we infer that there was predominant activation of the network responsible for velocity storage by electrical stimulation at many sites in the VN. Microstimulation at sites in PPH elicited nystagmus with ipsilateral slow phases or ipsilateral eye deviations. Slow phase eye velocity changed rapidly at the onset of nystagmus, and peak eye velocities were about 10–15°/s lower than from VN stimulation. The nystagmus had no slow component, and it was not followed by after-nystagmus. Only burst or burst-tonic neurons were recorded in PPH. Stimulation at sites of recording of these units induced either nystagmus with a rapid component or ipsilateral eye deviation. We conclude that the slow component of optokinetic and vestibular nystagmus, attributable to velocity storage is produced in the VN, not in the PPH. We postulate that VO neurons lying in caudal ventral portions of SVN, dorsal portions of MVN and adjacent LVN are part of the network that generates velocity storage.