实验性哮喘豚鼠初级传入系统和中枢内NKB的变化(英文)

本文应用放射免疫分析方法，测定了16只哮喘豚鼠初级传入系统和中枢内神经激肽β（NKB）的水平。结果表明，与正常对照组（结状神经书3228±11．89，C7～C8段脊神经节23．63±13．26，T1～T2段脊神经节24．25±1819，T3～T5段脊神经节25．53±12．34，C7～T5段脊髓后角28．65±16．59，孤束核26．34±18．36Pg／gwettissue）相比较，哮喘豚鼠初级传入系统和中枢内（结状神经节43．26±12．35，C7～C段脊神经节32．53±17．63，T1～T2段神经书32.25±20．65，T3～T5段脊神经节34．36±15．33，C7～T5段脊髓后角39．53±2028，孤束核3662±17．85Pg／gwettissue）NKB的含量明显高于对照组（P＜0．05）。结合NKB在呼吸道的作用，这些结果提示，初级传入系统和中枢内的NKB可能参与哮喘发病的病理生理机制。     

摘除双侧眼球对大鼠视交叉上核节律性的影响

成年Ｗｉｓｔａｒ雌鼠５７只，随机分为实验组３０只，行双眼摘除术。对照组２７只。术后４周将各组动物体重相近的每３只列为一个配伍组，分别在０９：００～１０：００、１７：００～１８：００、２３：００～２４：００三个时间处死。将含有视交叉上核的脑组织经固定、恒冷箱切片后，用免疫组化ＡＢＣ法染色显示视交叉上核内含ＶＩＰ或ＡＶＰ的神经元，微机图像分析仪上测量光镜下这两种神经元的相对切面面积及平均免疫反应强度。结果：（１）对照组不同时间处死的动物ＶＩＰ能神经元切面面积以２３：００～２４：００最大，０９：００～１０：００次之，１７：００～１８：００最小，呈昼夜节律变化，ＡＶＰ能神经元也以２３：００～２４：００最大，但在０９：００～１０：００和１７：００～１８：００间差异无显著性；（２）摘除双眼后各时间组间ＶＩＰ能神经元和ＡＶＰ能神经元切面面积均不再显示显著性差异。提示实验组动物视交叉上核的这两种神经元功能活动的昼夜节律已发生改变；（３）实验组和对照组动物的ＶＩＰ能神经元和ＡＶＰ能神经元平均免疫反应强度在所测的三个时间中，均未见明显差异。     

Ascending and descending internuclear connections of the trigeminal sensory nuclei in the cat. A study with the retrograde and anterograde horseradish peroxidase technique

The distribution of cells of origin of ascending and descending internuclear connections in the trigeminal sensory nuclei was studied by the retrograde horseradish peroxidase technique in the cat. The termination of collaterals of these ascending axons was also studied by the anterograde transport of horseradish peroxidase. Following injections of horseradish peroxidase into the ventral part of the principal sensory nucleus and the adjacent reticular formation many small neurons were labeled ipsilaterally in the whole area of the caudal portion of the nucleus interpolaris and in laminae III and IV of the nucleus caudalis. Labeled neurons were also found in laminae I and V. Injections limited to either nucleus oralis, the ventral part of the principal sensory nucleus and the medial parabrachial nucleus labeled similar types of neurons in the above regions with a topographic relationship; neurons in the dorsal part of the nuclei caudalis and interpolaris project, dorsally, to rostral portions of the trigeminal sensory nuclei while those in the ventral part of the nuclei caudalis and interpolaris project ventrally. Anterograde labeling of axons arising from the nucleus caudalis demonstrates that the axons ascend in the intranuclear bundles and the adjacent reticular formation, and give off collaterals to the nuclei interpolaris and oralis, and the ventral part of the principal sensory nucleus. Injections limited to the nucleus caudalis labeled small neurons in the rostral portion of the nucleus oralis and the caudal portion of the nucleus interpolaris. The present study suggests that these ascending and descending internuclear connections of the trigeminal sensory nuclei may modulate transmission of afferent inputs to various projection sites, such as thalamus, superior colliculus, cerebellum and spinal cord.     

Methylcobalamin induces a long-lasting enhancement of the field potential in rat suprachiasmatic nucleus slices

Optic nerve stimulation has been reported to evoke a field potential (FP) in rat suprachiasmatic nucleus (SCN) slices. Methylcobalamin,δ-(5,6-dymethylbenzimidazoyl)-Co-methyl-cobamide (Me-B₁₂) enhanced this FP and the enhancement lasted more than 1 h after washing out. Maximal enhancement (143.6±9.8%) was achieved at a concentration of 10 μM. By contrast, cyanocobalamin containing CN- instead of CH₃-showed no enhancement of the amplitude in the FP. Me-B₁₂ induced enhancement of FP was strongly blocked by an N-methyl- -aspartate (NMDA) receptor antagonist, -2-amino-5-phosphonovaleric acid (APV). These results indicate that CH₃- in the Me-B₁₂ is required to modulate the FP amplitude and the NMDA receptor is involved in the long-lasting FP enhancement induced by Me-B₁₂. The present results suggest that Me-B₁₂ modifies the photic entrainment of the circadian clock in the suprachiasmatic nucleus via an activation of NMDA receptors.     

白细胞介素—1对大鼠下丘脑室旁核Fos癌蛋白和CRF的诱导作用

将白细胞介素-1(IL)注入大鼠侧脑室,用Fos癌蛋白抗体免疫组化法检测了下丘脑室旁核的激活神经元:大量位于含促肾上腺皮质激素释放因子(CRF)相应区域的室旁核小细胞部神经元呈Fos免疫强阳性。Fos和CRF的免疫双染色显示了许多Fos免疫阳性神经元也呈CRF免疫阳性。此外,在IL-1注射动物中,CRF的免疫阳性显著加强,提示CRF合成增加。     

Electrophysiology of supraoptico-paraventricular nucleus connections in the rat

Summary In an attempt to clarify the mechanisms involved during synchronous discharge of magnocellular neurosecretory cells of the supraoptic and paraventricular nuclei, extracellular action potentials were recorded from 149 single units located in the rat paraventricular nucleus. Responses of the cells to stimulation of the ipsilateral supraoptic nucleus were recorded and it was observed that 7% of paraventricular nucleus neurones could be antidromically identified as projecting to the supraoptic nucleus. Excitatory responses were recorded from 40% of cells tested and were probably mediated by an interneurone population. Inhibitory responses were recorded from 37% of the cells and may have been mediated by direct projections from the supraoptic nucleus. No differences in responses were recorded from cells identified as projecting to the median eminence or neurohypophysis as compared with the rest of the population tested. However, more of the phasically firing putative vasopressin-secreting cells, (58%) were excited than were continuously active cells (38%). Delivery of short trains of high-frequency stimulation induced bursts of discharge from 93% of cells so tested, regardless of response to single shock stimulation. These burst discharges showed a late onset as compared with responses following single shock stimulation. The results suggest that a complex of intra- and internuclear interactions serve to regulate the neurosecretory activity of magnocellular cells within the supraoptic and paraventricular nuclei.     

Projections from the nucleus of the solitary tract in the rat

The axonal projections of neurons in and near the nucleus of the solitary tract have been visualized using titrated amino acid autoradiography. Axons of neurons of this nucleus ramify extensively within the nucleus itself, but much less so in the nucleus commissuralis. They also enter cranial motor nuclei within the medulla. Axons originating in the anterior part of the nucleus of the solitary tract extend to the hypoglossal, facial and probably trigeminal motor nuclei, but not to the dorsal motor nucleus of the vagus or the nucleus ambiguus. The posterior part of the nucleus of the solitary tract projects to all these motor nuclei. In the spinal cord solitary nucleus axons remain in the medial gray directly caudal to the solitary nucleus itself. The distribution becomes very weak by C₃ after some fibers spread laterally into the caudal trigeminal nucleus. Fibers are labeled in the contralateral ventral columns, but they could not be unequivocably attributed to solitary neurons. Axons ascending from the nucleus of the solitary tract extend no further rostrally than the pons, where they terminate in the caudal end of the parabrachial nuclei.Although often treated as entirely separate systems, the present results indicate that secondary gustatory neurons in the anterior solitary nucleus and secondary visceral afferent neurons in the posterior solitary nucleus have very similar rostral and caudal projections. The pontine parabrachial nuclei, the rostral termination of solitary nucleus neurons, have extensive direct connections to the thalamus, the hypothalamus and the limbic forebrain. Assuming similar connections occur in other mammals, these findings establish the existence of di-synaptic visceral afferent access to the highest autonomic integrative centers in the brain.     

PENA方法的建立及与ELISA IgM检测CMV的比较

目的　介绍一种敏感、稳定、快速、简便的实验室检测CMV的方法 ,同时探讨该种新方法与ELISA检测CMV方法的优、缺点。方法　对 5 5 2例病人应用间接荧光免疫法测定细胞核中的特异病毒早期抗体 (PENA)和ELISA法测定IgM抗体。结果　PENA方法 :强阳性 88例 ,阳性率 15 4 9% ,弱阳性 2 73例 ,阳性率 5 9 4 6 % ;ELISA -IgM方法 :阳性 34例 ,阳性率6 16 %。结论　PENA方法操作简便 ,与ELISA方法相比较 ,可对CMV感染进行早期测定及诊断 ,并可区分既往感染和即时感染 ,具有敏感性和稳定性 ,是测定小儿CMV感染的一种较好的方法     

In vivo and in vitro effects of imidacloprid on sheep keds (Melophagus ovinus): a light and electron microscopic study

The effects of imidacloprid (Advantage) on sheep keds (Melophagus ovinus Linné 1758) were studied in vivo and in vitro by means of direct observation (monitored on video tape) and by light and electron microscopy. It was found that: 1. Imidacloprid acted rapidly on all motile stages of the sheep keds. Within 3–4 min after exposure they became immobile and their legs and the abdomen started tetanic trembling movements for 15–30 min, leading to death. 2. The compound is apparently taken up by the body, since it also acted on those sheep keds that had been exclusively exposed to imidacloprid-contaminated filter papers. 3. The compound is available and active for more than 1 month in the wool of sheep; even rainfall does not reduce its efficacy. Body contact between treated mother sheep and their lambs protects them from infestation with these ectoparasites. 4. The compound initiates an ultimately lethal destruction of the ganglia, nerve chords and related muscle fibers, as can be seen in electron micrographs. Received: 7 October 2000 / Accepted: 18 October 2000