Multiple endocrine cell types in thyroid medullary carcinoma

Summary 10 cases of thyroid medullary carcinoma (TMC) have been studied ultrastructurally and histochemically. Well differentiated calcitonin-producing C cells were present in all tumours, being prevalent in 9 cases. 5-Hydroxytryptamine (5HT) storing cells were found in two cases, somatostatin immunoreactive cells in at least 5 cases and ACTH-immunoreactive cells in 4 cases. Ultrastructurally, at least 3 types of apparently non-C cells were observed. Type 1 cells with large, poorly osmiophilic granules resembling those of gastroenteropancreatic D cells, were present in 6 cases; they appeared to correlate well with somatostatin immunoreactive cells. Type 2 cells with large osmiophilic granules were found in 5 cases; they resembled ACTH-MSH cells of the human pituitary and may correspond to the ACTH-immunoreactive cells of light microscopy. Type 3 cells with small granules and an unknown function were found in 6 cases, always in scarce number. It is concluded that TMC, although mainly made up of C cells, usually contains large proportions of other endocrine cell types.Supported in part by grant N. 75.00630.04 from the Italian National Research Council (C.N.R.). P.F. is a fellow of the Fondazione Anna Villa Rusconi, Varese     

大鼠孤束核内5-HT能纤维和终末与向臂旁核投射的NOS阳性神经元的联系

应用四甲基罗达明逆行标记和免疫荧光技术相结合 ,在激光扫描共聚焦显微镜下对大鼠孤束核内 5 -HT能纤维和终末与向臂旁核投射的 NOS阳性神经元之间的联系进行了观察。将四甲基罗达明注入一侧外侧臂旁核后可见孤束核尾段背内侧、胶质、小细胞、内侧、中间内侧等亚核和连合亚核内出现较多的逆标神经元 ,四甲基罗达明逆标和 NOS阳性神经元以及 5 -HT阳性终末重叠分布 ,其中四甲基罗达明和 NOS双重阳性神经元分别占四甲基罗达明逆标和 NOS阳性神经元总数的 8.3% ( 14 /16 8)和 18.4% ( 14 /76 )。在此 5 -HT样阳性纤维和终末包绕着 NOS阳性神经元、四甲基罗达明逆标神经元及四甲基罗达明和一氧化氮合酶双重阳性神经元的胞体和树突 ,形成点状紧密接触。本研究结果提示 ,孤束核内来自下行性抑制系统的 5 -HT能纤维和终末可能与向臂旁核投射的 NOS阳性神经元形成突触联系 ,从而可对 NOS阳性神经元所传递的包括伤害性信息在内的内脏感觉传入信息发挥抑制性调控作用     

Differential involvement of GABA system in mediating behavioral and neurochemical effect of acupuncture in ethanol-withdrawn rats

In our previous study we demonstrated that acupuncture at Shenmen (HT7) points suppressed a decrease of accumbal dopamine (DA) release in ethanol-withdrawn rats. Furthermore, here we found that it inhibited behavioral withdrawal signs of ethanol. In an effort to better understand the mechanisms underlying this inhibition, the potential role of GABA receptor system in acupuncture was investigated. Male Sprague–Dawley rats were treated with 3 g/kg/day of ethanol (20%, w/v) or saline by intraperitoneal injection for 21 days. Following 48 or 72 h of ethanol withdrawal, acupuncture was applied at bilateral HT7 for 1 min. The selective GABA_A antagonist bicuculline and the selective GABA_B antagonist SCH 50911 were injected intraperitoneally 20 min before acupuncture, respectively. Importantly, suppressive effects of acupuncture on DA deficiency were completely abolished by SCH 50911, but not by bicuculline, whereas ameliorating effects of acupuncture on ethanol withdrawal syndrome were completely blocked either by SCH 50911 or bicuculline. These results suggest that acupuncture at specific acupoint HT7 may normalize the DA release in the mesolimbic system and attenuate withdrawal syndrome through the GABA_B receptor system in ethanol-withdrawn rats.     

Ca2+ permeability of the plasma membrane induced by rotavirus infection in cultured cells is inhibited by tunicamycin and brefeldin A

Rotavirus infection of cultured cells induces a progressive increase in plasma membrane permeability to Ca2+. The viral product responsible for this effect is not known. We have used tunicamycin and brefeldin A to prevent glycosylation and membrane traffic and study the involvement of viral glycoproteins, NSP4 and/or VP7, in rotavirus-infected HT29 and MA104 cells. In infected cells, we observed an increase of plasma membrane Ca2+ permeability and a progressive depletion of agonist-releasable ER pools measured with fura 2 and an enhancement of total Ca2+ content measured as 45Ca2+ uptake. Tunicamycin inhibited the increase in membrane Ca2+ permeability, induced a depletion of agonist-releasable and 45Ca2+-sequestered pools. Brefeldin A inhibited the increase of Ca2+ permeability and the increase in 45Ca2+ uptake induced by infection. We propose that the glycosylated viral product NSP4 (and/or VP7) travels to the plasma membrane to form a Ca2+ channel and hence elevate Ca2+ permeability.     

大鼠神经系统内5-HT5A受体亚型的定位分布

目的：观察大鼠神经系统内5－HT5A受体亚型（5－HT5AR）的定位分布。方法：5－HT5AR特异性抗体的免疫细胞化学染色技术。结果：5－HT5AR阳性元主要分布于斜角带核、终纹床核、视上核、室旁核、下丘脑前区、下丘脑腹内侧核、下丘脑外侧区、弓状核、视产叉上核、乳头体上核、杏仁基外侧核、蓝斑、面神经核、舌下神经核、中缝隐核、中 缝苍白核、孤束核以及三叉神经节和脊神经节。结论：5－HT5AR阳性结构比较广泛地分布于大鼠神经系统,5－HT可能通过5－HT5AR实现对神经系统多种功能活动的调控。     

视网膜无长突细胞5—HT免疫组织化学研究

用免疫,组织化学ＡＢＣ法研究了５－ＨＴ免疫阳性反应在牛蛙视网膜细胞中的分布。结果人核层内一些无长突细胞及内网层呈阳性反应。根据阳性胞体在内核层的部位和胞体的突起在内网层的分布,鉴别出６种无长突业刑。提示无长突细胞可能在５－ＨＴ信号的传递和调控过程中发挥着重要作用。     

氧化低密度脂蛋白、低氧和5-HT对血管平滑肌细胞5-HT2A受体及胞内游离钙的影响

目的　为探讨粥样硬化病变动脉对 5 - HT收缩反应增加的机制 ,观察与粥样硬化有关因子氧化低密度脂蛋白 (ox L DL)、低氧、5 - HT对血管平滑肌细胞 5 - HT2 A受体及其基因表达 ,以及细胞 [Ca2 ]i的效应。方法　分别将大鼠主动脉平滑肌细胞单独以 5 0 μg/ m l ox L DL 培养 8h,2 %低氧处理 2 4和 48h,10 μm ol/ L 5 - HT处理30 min,放射配基结合分析测定 5 - HT2 A受体 ;RT- PCR和 Southern杂交检测受体基因的 m RNA;激光共聚焦扫描显微镜测单个细胞 [Ca2 ]i。结果　经 ox L DL、低氧、 5 - HT处理 ,血管平滑肌细胞 5 - HT2 A受体显著上调 (P<0 .0 1) ;ox L DL及低氧处理的受体基因的 m RNA表达增加 ;ox L DL、低氧处理后 ,5 - HT刺激的血管平滑肌细胞[Ca2 ]i升高幅度显著加大 (P<0 .0 5及 P<0 .0 1)。结论　 ox L DL、低氧、5 - HT引起血管平滑肌细胞 5 - HT2 A受体上调及细胞 [Ca2 ]i增加 ,可能是粥样硬化动脉对 5 - HT收缩反应增强的部分原因。     

Kentanserin对大鼠心肌缺血 再灌注损伤的影响

为探讨５ ＨＴ２受体与心肌缺血 再灌注损伤的关系,观察５ ＨＴ２受体阻断剂ｋｅｎｔａｎｓｅｒｉｎ对心肌缺血 再灌注大鼠室颤及左室内压＋ｄｐ／ｄｔｍａｘ及－ｄｐ／ｄｔｍａｘ的影响。结果表明,ｋｅｎｔａｎｓｅｒｉｎ可拮抗缺血性心功能障碍和再灌室颤。提示５ ＨＴ２受体参与了缺血性心功能障碍和再灌室性心律失常的发生。     

TMB-8抑制5-HT和KCl引起大鼠脑血流量减少

目的研究TMB-8对5-HT和KCl引起的大鼠脑血流量(CBF)减少的作用。方法用激光多普勒血流仪测量大鼠CBF,在人工脑脊液灌流液中加入TMB-8和工具药进行干预。结果12.5, 25和50 μmol·L^-1 TMB-8对大鼠CBF无明显影响,TMB-8可抑制5-HT引起的大鼠CBF减少。在1 μmol·L^-1 5-HT引起大鼠CBF持续下降的状态下,TMB-8可浓度依赖的增加大鼠CBF。TMB-8也可抑制KCl引起的大鼠CBF减少。在20 mmol·L^-1 KCl引起大鼠CBF持续下降的状态下,TMB-8可浓度依赖的增加大鼠CBF。结论TMB-8可抑制5-HT和KCl引起的大鼠CBF减少,也可浓度依赖的增加被5-HT和KCl所减少的大鼠CBF,改善大鼠缺血区脑血供。     

孕妇广泛焦虑障碍和血浆DA、NE、5-HT的相关研究

目的 :探讨分娩前孕妇广泛性焦虑障碍与血浆 5 - HT、DA、NE的关系。方法 :首先用心理卫生量表 (SAS、SDS、HAMA、HAMD)筛查孕妇中存在广泛性焦虑和抑郁共病共 4 6例。研究组血浆中五羟色胺 (5 - HT4 6例 )、去甲肾上腺素 (NE4 6例 )、多巴胺 (DA4 5例 )和正常对照组 (5 - HT、DA、NE各 2 0例 )由苏州大学生化工程研究所采用高效液相色谱仪、电化学检测器进行测定。结果 :分娩前孕妇广泛性焦虑障碍血浆 5 - HT、DA、NE和对照组未见明显差异。讨论 :我们在产前经 SAS、HAMA检测发现产前孕妇广泛性焦虑障碍有 74例。我们选择了资料完整诊断明确的产前广泛性焦虑进行了血浆 5 - HT、NE、DA测定结果发现与对照组没有明显差异 ,这说明孕妇在临床上焦虑症状明显 ,但体内血浆神经介质极不稳定 ,神经介质变化在人体内较为复杂 ,使两者没有变化 ,提示孕妇广泛性焦虑障碍患者存在外周交感神经兴奋性增高 ,血浆 5 - HT、NE、DA浓度不能鉴别焦虑症。以上观点还需进一步研究。在妇产科广泛焦虑障碍这一疾病 ,应引起产科医师注意。