猫阴部神经传入传出成分在脊髓内的定位分布—HRP逆行及跨越神经节追踪研究

向猫阴部神经及其分支注入HRP溶液,观察并分析了逆行和跨节追踪的结果。 1.证实阴部神经为含躯体传出、传入,内脏传出、传入纤维的混合神经,其内脏性传出、传入成分仅存在于阴茎背神经中。 2.逆行标记细胞出现于L_7—S_3前角Onuf核和S_(1-3)的中间带外侧核。本文结果表明,Onuf核是支配盆底横纹肌的运动核,但它和其它前角运动核在细胞形态和活性物质的分布上都明显不同。特别是它的一部分神经元的树突形成树突束到达中间带外侧核。本文结合排尿、排便功能从形态学上较详细地讨论了Onuf核和中间带外侧核的关系。 3.本文证明阴部神经领域的内脏初级传入(来自阴茎背神经)和躯体初级传入纤维都向骶髓后连合核区有浓密的投射。结合以往的工作讨论了盆腔脏器、外生殖器的内脏传入和坐骨神经、阴部神经的躯体传入在骶髓后连合核区汇聚的现象及机能意义,推测这种汇聚可能是产生牵涉痛和针刺镇痛机制的形态学基础。     

成年大鼠基底前脑隔-斜角带复合体的巢蛋白免疫阳性神经元至海马的纤维投射

目的 观察大鼠基底前脑巢蛋白(nestin)免疫阳性神经元的纤维投射。方法 先用荧光素逆行追踪法显示基底前脑内投射至海马的荧光素标记神经元，观察摄片后再进行nestin免疫组织化学染色。对比荧光照片和免疫组织化学染色照片，辨认荧光素和nestin双标神经元。结果 在基底前脑注射侧的内侧隔核(MS)和斜角带核的垂直支(vDB)和水平支(hDB)均存在荧光素标记细胞，其中一部分为nestin免疫阳性。在MS、vDB和hDB，双标细胞占逆行标记细胞的比例分别为21．3％、25％和20．6％；占nestin阳性细胞的比例分别为26．6％、15．7％和16．3％。结论 大鼠基底前脑的nestin免疫阳性神经元发出神经纤维向海马投射。提示在基底前脑有一个平行于隔-海马胆碱能投射和GABA能投射的第3条通路。     

Postsynaptic fibers reaching the dorsal column nuclei in the rat

Postsynaptic fibers reaching the dorsal column nuclei were investigated in rat by means of retrograde transport of wheat germ agglutinin-horseradish peroxidase conjugate. Each nucleus received only ipsilateral afferents with most of the labeled cells forming a band which covered the mediolateral extent of the dorsal horn in an area that resembled lamina IV in the cat. The labeling excluded the reticular extension of the neck of the dorsal horn. Lumbosacral afferents were restricted to the gracilis nucleus and cervicothoracic afferents to the cuneatus nucleus. Cervical and anterior lumbar levels showed additional projections coming from their most medial parts. The organization of this second-order pathway in rat is similar to that in cat and monkey.     

Retrograde migration of glove powder in the human female genital tract

BACKGROUND: This study in humans was undertaken to evaluate earlier results from animal research showing a retrograde migration of glove powder from the vagina into the intra-abdominal cavity. METHODS: One study group was gynaecologically examined with powdered gloves the day before an abdominal hysterectomy and another group 4 days pre-operatively. There were two control groups similarly examined with powder-free gloves. Cell smears were taken from the peritoneal fluid and during the operation further smears were taken from the Fallopian tubes, uterine cavity and cervical canal. RESULTS: Statistically significant differences were found for large starch particles at all locations between the study and control groups examined 1 day pre-operatively. Considering small starch particles, there were significant differences in cervix (P < 0.001), uterus (P < 0.01) and the Fallopian tubes (P < 0.01). The combined results also show significant differences between both large and small starch particles in cervix, uterus and the Fallopian tubes. There were also differences between the study and control groups examined 4 days pre-operatively, but these were not statistically significant except for small and large starch particles in uterus (P < 0.01, P < 0.05) and cervix (P < 0.05, P < 0.05). CONCLUSIONS: This study has pointed out a retrograde migration of starch also in humans after a gynaecological examination with powdered gloves. Consequently, powder or any other potentially harmful substance that can migrate from the vagina should be avoided.     

大白鼠脊髓向延髓外侧网状核投射的体部定位——HRP顺行法研究

向大白鼠脊髓的颈、腰膨大和胸髓右侧半分别注入HRP或WGA—HRP,研究了脊髓向延髓外侧网状核的投射。 1.双侧的三叉神经下亚核同时接受颈、胸和腰髓来的投射。 2.大白鼠脊髓主要投射于外侧网状核的尾侧半,有一定的体部定位关系。颈髓投射于双侧大细胞亚核的外侧2/3及与共相邻接的一部分小细胞亚核内,以同侧投射为主。胸髓投射于双侧的大细胞亚核的内侧2/3和与之相邻接的一部分小细胞亚核内,两侧无明显差別。腰髓投射于双侧小细胞亚核和与之相邻接的部分大细胞亚核内,以对侧投射为主。它们相互间有部分重叠。 3.颈、胸和腰髓内外侧网状核投射的神经元位于从背角至腹角的灰质内,越边投射的神经元比不越边投射的神经元位置更靠腹侧。     

Monosynaptic inputs from the nucleus tractus solitarii to the laryngeal motoneurons in the nucleus ambiguus of the rat

The cricothyroid (CT) and the posterior cricoarytenoid (PCA) muscles in the larynx are activated by the laryngeal motoneurons located within the nucleus ambiguus; these motoneurons receive the laryngeal sensory information from the nucleus tractus solitarii (NTS) during respiration and swallowing. We investigated whether the neurons in the NTS projected directly to the laryngeal motoneurons, and what is the synaptic organization of their nerve terminals on the laryngeal motoneurons using the electron microscope. When wheat germ agglutinin-conjugated horseradish peroxidase (WGA-HRP) was injected into the NTS after cholera toxin subunit B-conjugated HRP (CT-HRP) was injected into the CT muscle or the PCA muscle, the anterogradely WGA-HRP-labeled terminals from the NTS were found to directly contact the retrogradely CT-HRP-labeled dendrites and soma of both the CT and the PCA motoneurons. The labeled NTS terminals comprised about 4% of the axosomatic terminals in a section through the CT motoneurons, and about 9% on both the small (PCA-A) and the large (PCA-B) PCA motoneurons. The number of labeled axosomatic terminals containing round vesicles and making asymmetric synaptic contacts (Gray’s type I) was almost equal to that of the labeled terminals containing pleomorphic vesicles and making symmetric synaptic contacts (Gray’s type II) on the CT motoneurons. The labeled axosomatic terminals were mostly Gray’s type II on the PCA-A motoneurons, while the majority of them were Gray’s type I on the PCA-B motoneurons. These results indicate that the laryngeal CT and PCA motoneurons receive a few direct excitatory and inhibitory inputs from the neurons in the NTS. Accepted: 2 June 2000     

Auditory corticocortical interconnections in the cat: evidence for parallel and hierarchical arrangement of the auditory cortical areas

Summary The origin and laminar arrangement of the homolateral and callosal projections to the anterior (AAF), primary (AI), posterior (PAF) and secondary (AII) auditory cortical areas were studied in the cat by means of electrophysiological recording and WGA-HRP tracing techniques. The transcallosal projections to AAF, AI, PAF and AII were principally homotypic since the major source of input was their corresponding area in the contralateral cortex. Heterotypic transcallosal projections to AAF and AI were seen, originating from the contralateral AI and AAF, respectively. PAF received heterotypic commissural projections from the opposite ventroposterior auditory cortical field (VPAF). Heterotypic callosal inputs to AII were rare, originating from AAF and AI. The neurons of origin of the transcallosal connections were located mainly in layers II and III (70–92%), and less frequently in deep layers (V and VI, 8–30%). Single unit recordings provided evidence that both homotypic and heterotypic transcallosal projections connect corresponding frequency regions of the two hemispheres. The regional distribution of the anterogradely labeled terminals indicated that the homotypic and heterotypic auditory transcallosal projections are reciprocal. The present data suggest that the transcallosal auditory interconnections are segregated in 3 major parallel components (AAF-AI, PAF-VPAF and AII), maintaining a segregation between parallel functional channels already established for the thalamocortical auditory interconnections. For the intrahemispheric connections, the analysis of the retrograde tracing data revealed that AAF and AI receive projections from the homolateral cortical areas PAF, VPAF and AII, whose neurons of origin were located mainly in their deep (V and VI) cortical layers. The reciprocal interconnections between the homolateral AAF and AI did not show a preferential laminar arrangement since the neurons of origin were distributed almost evenly in both superficial (II and III) and deep (V and VI) cortical layers. On the contrary, PAF received inputs from the homolateral cortical fields AAF, AI, AII and VPAF, originating predominantly from their superficial (II and III) layers. The homolateral projections reaching AII originated mainly from the superficial layers of AAF and AI, but from the deep layers of VPAF and PAF. The laminar distribution of anterogradely labeled terminal fields, when they were dense enough for a confident identification, was systematically related to the laminar arrangement of neurons of origin of the reciprocal projection: a projection originating from deep layers was associated with a reciprocal projection terminating mainly in layer IV, whereas a projection originating from superficial layers was associated with a reciprocal projection terminating predominantly outside layer IV. This laminar distribution indicates that the homolateral auditory cortical interconnections have a feed-forward/feed-back organization, corresponding to a hierarchical arrangement of the auditory cortical areas, according to criteria previously established in the visual system of primates. The principal auditory cortical areas could be ranked into 4 distinct hierarchical levels. The tonotopically organized areas AAF and AI represent the lowest level. The second level corresponds to the non-tonotopically organized area AII. Higher, the tonotopically organized areas VPAF and PAF occupy the third and fourth hierarchical levels, respectively.Abbreviations AAF anterior auditory cortical area - AI primary auditory cortical area - AII secondary auditory cortical area - BF best frequency - C cerebral cortex - CA caudate nucleus - CL claustrum - D dorsal nucleus of the dorsal division of the MGB - ea anterior ectosylvian sulcus - ep posterior ectosylviansulcus - IC internal capsule - LGN lateral geniculate nucleus - LV pars lateralis of the ventral division of the MGB - LVe lateral ventricule - M pars magnocellularis of the medial division of the MGB - MGB medial geniculate body - MGBv ventral division of the MGB - OT optic tract - OV pars ovoidea of the ventral division of the MGB - PAF posterior auditory cortical area - PH parahippocampal cortex - PO lateral part of the posterior group of thalamic nuclei - PU putamen - RE reticular complex of thalamus - rs rhinal sulcus - SG suprageniculate nucleus of the dorsal division of the MGB - ss suprasylvian sulcus - TMB tetrametylbenzidine - VBX ventrobasal complex - VLa ventrolateral complex - VL ventro-lateral nucleus of the ventral division of the MGB - WGA-HRP wheat germ agglutinin conjugated to horse-radish peroxidase - WM white matter - VPAF ventro-posterior auditory cortical area     

Fluorescent retrograde triple labeling of brainstem reticular neurons

The present study was aimed at the anatomical identification in the rat of neurons of the lower brainstem reticular formation which give off axonal branches ascending bilaterally to more rostral structures and descending unilaterally to the spinal cord. Three fluorescent tracers were injected in one and the same animal. Fast Blue was injected in the midbrain tegmentum, in the termination areas and fiber bundles of the ascending reticular efferents; Evans blue was injected in the midbrain tegmentum on the other side; either Nuclear Yellow or Diamidino Yellow was injected in the white and gray matter of the upper cervical cord. All three populations of single-labeled cells, as well as double labeled either from the midbrain injections or from the ipsilateral injections in the mesencephalon and spinal cord, were intermingled in the medial reticular formation. Very few cells double labeled from the contralateral mesencephalon and ipsilateral spinal cord were also seen. However, the main finding of the present study was the visualization of triple-labeled cells. The latter were mainly located ipsilaterally to the injections in the spinal cord. The present results indicate that reticular cells give off divergent multiple branches descending to the ipsilateral spinal cord and ascending bilaterally to rostral centers.     

Nitric oxide synthase neurons in the rodent spinal cord: distribution, relation to Substance P fibers, and effects of dorsal rhizotomy

The indirect immunofluorescent method was employed to investigate the distribution of neuronal nitric oxide synthase-like immunoreactivity(nNOS-LI) in the spinal cord of the golden hamster and to compare it to data obtained from rats. Immunoreactive neurons were found throughout the cervico-sacral extent in the dorsal horn (mainly in laminae I-III) and in the preganglionic autonomic regions, i.e., the sympathetic intermediolateral nucleus (IML), lateral funicle (LF), intercalated region (IC), the area surrounding the central canal (CA), and the sacral preganglionic parasympathetic cell group. While the distribution of immunoreactive cells was generally similar in both species, some differences were observed. For example in the hamster LF, a higher percentage of stained neurons was seen than in the IML, while the situation was rather inverse in the rat. In order to study the coincidence of nNOS-LI in the population of preganglionic sympathetic neurons (PSN) that innervate the superior cervical ganglion (SCG), these were identified by retrograde axonal transport of fluoro-gold (FG) following unilateral injection into the SCG. PSN were localized ipsilateral to the injection site mainly in the IML and LF of spinal segments C7-Th4. The portion of double-labeled neurons of the IML were lower in hamster (17% in C7, 34% in C8) of FG-labeled cells) than in rat (47% in C8, 77% in Th2), while in the LF of segments C8-Th2 in both species the majority of FG-neurons contained nNOS. While only very few double-labeled neurons were detected in the IC in hamster and rat, a striking difference was observed in the CA, where no double-labeled neurons were found in hamster, but up to 50% in rat. Double immunofluorescence detection of nNOS and substance P (SP) showed that in both the autonomic regions and the dorsal horn, SP-LI fibers and puncta were present in close spatial relationship to nNOS-LI cell bodies. These results were basically identical in the hamster and rat. Unilateral transection of the dorsal roots of segments C6-Th2 in rats resulted in a clear reduction of SP-LI structures in the dorsal horn 5 days after rhizotomy, but not in the autonomic regions. Compared to the unlesioned side, the numbers of nNOS-LI neurons in the superficial laminae of the dorsal horn were reduced to 32-46% in the lesioned segments, and to 53% and 87%, respectively, in the two segments cranial to the rhizotomized segments but remained unchanged caudally to the lesion. Numbers of nNOS-LI cell bodies in the autonomic regions were not altered following dorsal root transection. The present study provides data on the widespread distribution of nNOS in the spinal cord of golden hamster and describes the partial coincidence of the enzyme in PSN. The effects of dorsal rhizotomy on nNOS-LI neurons in the dorsal horn reveal that primary-afferent fibers provide a stimulatory influence on neurons of the dorsal horn to generate the gaseous neuroactive substance, nitric oxide.     

逆行带锁髓内钉治疗股骨远端骨折的应用解剖

目的:为带锁髓内钉治疗股骨远端骨折提供形态学基础。方法:①选用30例成人干燥股骨测量股骨内外侧髁、内外上髁、髁间窝有关数据进行统计分析。②20侧下肢标本解剖观测膝降动脉及隐神经髌下支的分支、分支等及两者的关系。结果:髁间窝呈U型占35%,V型占65%,此窝最宽处横径:左侧(1.98±0.36)cm, 右侧(2.06±0.29) cm;内侧髁后关节面宽,左侧(2.21±0.23) cm,右侧(2.34±0.29) cm;内、外上髁的距离,左侧(7.30±0.60)cm,右侧(7.43±0.57)cm。膝降动脉髌下支和隐神经髌下支呈紧密的伴行关系。隐神经在缝匠肌中下1/3交界点穿出,有上、下两支分布到膝关节前外侧皮肤。结论:术中注意这些解剖位置特点,避免损伤神经和血管,减少手术出血,防止并发症。