ABSTRACT
Eighteen adult rabbits(0 9and 0 9, body weights 1.5～2kg) were selected for the present study. A solution of 5～15% HRP(RZ=2.9) 10% EB (Evans Blue) and 7% TY (Titan Yellow)was respectively injected into the subserosa of genital glands in fourteen rabbits and a solution of 35% HRP into the tibial nerves of the Sanyinchiao regions in other four rabbits. The uptake and retrograde transmission of HRP and of EB and TY in the afferent fibres of both the somatic and visceral nerves were traced to the spinal ganglia. In addition, anterograde transport were verified by using ARG method in two cats. The range of segments where the neurons give off these two afferent fibres overlap each other. The results were as follows: 1. The labelled sensory neurons from the region of the testis where HRP was injected were observed more concentrated in the spinal ganglia T11～L4, and the ovary in the spinal ganglia T10～L14. 2. The labelled neurons from the region of Sanyinchial were found more concentratedly in the spinal ganglia L_4～S_3. 3. The ranges of distribution of labelled neurons from the two groups of afferent fibres overlap in segment T7～L7.
ABSTRACT
The segmental distribution of sensory and motor neurons in Neiguan (内关P6) acupoint areas was studied respectively in 8 rabbits with a horseradish peroxidase (HRP) method. The labeled neurons were found in C5-T1 segments of the spinal ganglia and in C7-T1 segments of the spinal cords (injected sides). Most labeled neurons were found concentrated in C8 and T1 of the spinal ganglia, and principally located in the circumferental areas of the spinal ganglia (47.27%). In spinal cord, the labeled neurons were located in the lateral areas of the ventral horns and the juncture of it and the lateral horns (Ⅷ-Ⅸlayers). In addition, the relation of the relative specifity of acupoints to the distributional segments of the neurons and its concentration was discussed.
ABSTRACT
HRP solution was injected into the dorsal commissural nucleus (DCN) of segment L_6 or S_1 of the spinal cord and laterodorsal tegmental area(TLD)——take the Barrington's nucleus as its center and lateral parabrachial nucleus (PBL) of the rostral pons in different individuals of the rats. After HRP was injected into the DCN, labelled neurons and dense terminals were found in Barrington's nucleus, and labelled terminals appeared in the PBL. When the unilateral TLD was injected the labelled cells and terminals were found in the DCN and bilateral intermediate zone (IM), and formed a band of labelled neurons and terminals. When the PBL was injected the labelled neurons were observed in the DCN and bilateral IM. A few labelled neurons were found in lamina Ⅰ in the latter two experimental groups.Based on the present and previous studies, the authors got the following understandings:1. Morphylogically, the present study for the first time demonstrated that, the micturition reflex arch through the pontine consists of following parts: the primary afferent neurons of the bladder→secondary relay neurons of DCN→Barrington's nucleus→IM (mainly IML) parasympathetic preganglionic neurons→parasympathetic postganglionic neurons.2. According to the present and previous researches, the authors conjecture that, the secondary fibers of visceral sensation of the pelvic organs originate from the neurons of DCN, IM and lamina I and project into the PBL.3. According to the facts mentioned above, we presume that the DCN and bilateral IM constitute a complex and named it the 'visceral field', and which is closely associated with the pelvic organs. This field has widespread connections with the peripheral efferent and afferent nerves. On the other hand, i t contains a lot of relay neurons projecting into Barrington's nucleus and PBL and receives the terminals of descending fibers of the neurons of the Barrington's nucleus. The descending fibers also project into the Onuf's nucleus.In addition, the present study disscussed the complicated functions of the DCN systematically.
ABSTRACT
The afferent projections of the prefrontal cortex(PFC) from the cerebral cortex were studied using WGA-HRP technique in 25 rats. The PFC of the rat re- cieved the afferent projections widely arising from the frontal, parietal,temporal, occipital, cingulate, piriform and retrohippocampal cortex. Furthermore,the dif- ferent organizations of the cortical afferent projections of the medial and lateral part of the PFC were also found. Besides the afferents from the somatic and visceral sensory cortex, the PFC of rat also recives afferents of visual and auditory cortex and it appears to be a multiple sensory convergence area.
ABSTRACT
HRP solution (33%) was injected into the left superior colliculus of 21 adult albino rats. 1-2 days after injection, the animal was sacrificed. Brains were frozen sectioned and processed according to. DAB- or TMB-method. The labeled neurones were examined in the right superior colliculus and other areas of the brain. The resu ts are as follows:1. No matter where the HRP was injected (either in the rostral or caudal part of the superior colliculus or thepart between them) HRP labeled neurones were always observed on the opposite superior colliculus if the injection sites reached layers deeper than the stratum oPticum. The locations of the labeled neurones corresponded roughly to the sites of HRP injections. However, no HRP labeled neurones were observed when the core of HRP deposites was restricted to layers superficial to the stratum griseum intermediale.2. Of all labeled neurones, 53.6% were located in the stratum griseum intermediale, 16.5% in the stratum opticum. The rest were in deeper layers. In no case were HRP labeled neurones observed in the stratum zonale or stratum griseum superficiale.3. Labeled neurones could be classified morphologically into vertical fusiform, horizontal fusiform and multipolar neurones.4. In addition to the visual cortex, labeled neurones were also found in the inferior colliculi, paralemniscal nuclei, dorsal nuclei of the lateral lemniscus, substantia nigrae and lateral tegmental nuclei bilaterally. Labeled neurones were also found in the ipsilateral ventral nucleus of the lateral geniculate body, contralatera pretectal area and reticular formation.
ABSTRACT
0.05～0.2?l of HRP (Sigma Ⅵ) were introduced into the periaqueduetal gray (PAG) of 45 rats at the superior collicular level, each brain was sectioned and processed with DAB, BDHC, O-D and TMB reactions. 29 were chosen for analysis and according to the locations of the injection center and the extent of reaction, were divided into 3 groups:1. The injection center was found in the lateral part of PAG; the reaction only involved a small area within PAG (11 rats), labeled cells were seen in PAG, tectum, reticular formation (RF) and dorsal raphe nucleus.2. The injection center was in the dorsolateral part of PAG; the reaction area extended out of PAG to the nearby RF and tectum (9 rats); labeled cells were seen in the structures mentioned in group 1 as well as in habenular nucleus (hn), parafascicular nucleus (PFN), hypothalamic nuclei (anterior, posterior, ventromedial, dorsomedial, lateral), thalamic nuclei (lateral, reticular, medial part of ventral nucleus), paraventricular gray (PVG), nucleus of the optic tract, nucleus of posterior commissure (NPC), parabigeminal nucleus (PBN), locus ceruleus, ventral nucleus of lateral geniculate body, entopeduncular nucleus.3. The injection center was in the lateral or ventrolateral part of PAG, the reaction area extended to the nearby RF, tegmentum and part of tectum (9 rats), labeled cells were seen in the structures mentioned in group 1 as well as in substantia nigra, H_1, H_2, zona inserta, HN, PFN, PVG, NPC, PBN, locus ceruleus, pretectral area and nuclei of hypothalamus. In this group 3 rats were processed with TMB reaction. Labeled cells were seen not only in the above-mentioned structures but also in the deep layers of anterior cingulate cortex (areas 23 and 24), nucleus raphe magnus, nucleus reticularis gigantocellularis, periventricular gray of 4th ventricle, dentate nucleus of cerebellum, lamina Ⅴ～Ⅶ of cervical spinal cord (the other segments were left out), preoptic and supraoptic nuclei, suprachiasmatic nucleus, anterior nucleus of mammillary body, medial nucleus of amygdaloid nucleus, spinal nucleus of nerve Ⅴ. The labelled cells were seen chiefly in the ipsilateral side. Neuronal connections also were analysed according to the disparity in labelled structures.
ABSTRACT
The somatotopical pattern of the spinal projection to the lateral reticular nucleus (LRN) was examined in 16 rabbits. The anterograde transport of HRP method were used.1. Cervical, thoracic and lumbar segments all gave rise to small numbers of fibers projecting to bilateral lateral reticular subtrigeminal subnucleus (Lrs).2. Cervical, thoracic and lumbar projections to the LRN were bilateral but the cervical ascending fibers terminated predominately on the ipsilateral side. The lumbar ascending fibers projected chiefly to the contralateral side. The thoracic cord gave fibers to bilateral LRN. No significant difference could be seen between the two sides. There were certain overlapping among the distribution areas of the terminal branches from different parts of the cord.3. The spinal projections of the rabbit were predominately terminated in the caudal half of the LRN. It showed a somatotopical pattern. The cervical cord projected to the lateral 3/5 of the lateral reticular magnocellular subnucleus (Lrm) and its neighbouring part of the lateral reticular parvocellular subnucleus (Lrp). The thoracic cord projected to the medial 3/5 of the Lrm and its neighbouring part of Lrp. The lumbar cord gave afferents to the Lrp and its neighbouring part of Lrm.
ABSTRACT
The cortical distribution of thecells of origin of the corticotrigeminal projection to the oral subnucleus of spinal trigeminal nucleus(Vo)was examined with the HRP retrograde tracing method. The results showed that the coronal gyrus was the main site of origin. The anterior part and the posterior part of the gyrus projected to the dorsomedial portion and the ventrolateral portion of Vo respectively. The amount of labelled cells in the anterior part of the gyrus was much larger than those in the posterior. There were also numerous labelled cells in the anterior parts of orbital gyrus and of the lateral zone of anterior sigmoid gyrus. The most anterior ends of these three gyri joined together forming the so-called "presylvian gyrus" where the labelled cells were most concentrated. In addition, the labelled cells were also scattered in the anterior suprasylvian gyrus, posterior sigmoid gyrus, lateral gyrus and anterior ectosylvian gyrus. All labelled cells were located in the fifth layer of the cortex. Their size varied. The results of the present study did not support that there were projections from the temporal and occipital lobes and proreate gyrus to Vo.
ABSTRACT
The segmental distribution of the afferent fibers traversing the stellate ganglia was studied with HRP techinque in 33 cats. The animals were divided into two groups. In one group HRP was injected into the stellate ganglion of one side. Labelled cells were found in ipsilateral spinal ganglia from C_4 to T_9. The majority of these cells (84.49％) were distribued in T_1 to T_5 segments. There is no conspicuous difference between the left and right in respect to the segmental and the pattern distribution of labelled cells. The majority of the labelled cells were medium or small sized (
ABSTRACT
The present study was undertaken to identify some afferent connections of the ventral and dorsal parts of pontine tegmentum in guinea pigs by using horseradish peroxidase retrograde microelectrophoretic technique.After introducing HRP into the ventral part of pontine tegmentum, numerous labeled cells were observed in the mesencephalic central gray and related reticular formation, which is equivalent to the MSR (Mesencephalic Stepping Region) ventral to the surface of the superior colliculus. Labeled cells could also be identified at the following sites: nucleus cuneiformis ventral to the surface of inferior colliculus, nucleus tractus spinalis nervi trigemini, nucleus reticularis gigantocellularis, nucleus medialis vestibulares, nucleus lateralis vestibulares, nucleus loci coerulei and its ventral part, gray matter of the cervical enlargement of spinal cord.Following injection of HRP into the dorsal part of pontine tegmentum, substantial amount of labeled cells were observed in the nucleus reticularis pontis caudalis and nucleus reticularis gigantocellularis Labeled cells gould also be identi- fied in the nucleus medialis vestibulares, nucleus lateralis vestibulares and nucleus cuneatus. Only a few HRP cells appeared around the nucleus tuber in the midbrain and no labeled cells have been seen in the nucleus loci coerulei, as well as the gray matter of cervical spinal cord.
ABSTRACT
HRP solution was injected into the right side of the thoracic spinal cord of the rat with a micropipette to observe the neurons which give rise to the descending propiospinal tract. Labeled neurons were distributed throughout the bilateral Rexed's laminae Ⅰ-Ⅹ of the spinal cord in the segments rostral to the site of HRP application. The greatest number of the labeled cells were consistently found in lamina Ⅶ (including the intermediolateral nucleus), and then in laminae Ⅷ and Ⅳ. Our results verified the existence of the nucleus of the dorsolateral funiculus and its intraspinal connections in the spinal cord of the rat. This nucleus gives rise to the descending projections to the lower spinal segments.
ABSTRACT
The localization of the neurons which control the inferior oblique muscle in the oculomotor nucleus and their dendritic architecture were studied by injecting the conjugated cholera toxin-horseradish peroxidase (CT-HRP) into the inferior oblique muscle of 7 rabbits.The oculomotor nucleus could be divided into oral, middle and caudal parts. The middle part was further divided into dorsomedial and ventrolateral parts, and the caudal part divided into dorsal and ventral parts. The labeled neurons innervating the inferior oblique muscle were mainly distributed ipsilaterally and occupying two thirds. of the rostrocaudal extent of the oculomotor nucleus, a few were scattered contralaterally.The labeled cells were found in the dorsomedial part of the nucleus orally, and shifted in successive caudal sections to the medial and then to the ventral part. No labeled cells in the oral and caudal ends of the nucleus could be identified.The dendritic branches of the labeled neurons covered the whole nucleus, but densest in its dorsomedial part. Many of them extended beyond the boundary of the nucleus into the central gray matter dorsally, some even approacheding the aqueduct, or through the medial longitudinal fasciculus into the reticular formation laterally and ventrally. A few dendrites crossed the midline into the contralateral nucleus. Therefore the receptive field of the oculomotor nucleus is presumably much larger than the area of the nucleus itself.
ABSTRACT
The afferent connections and topographical organization of the central lateral nucleus were studied with HRP retrograde tracing technique in 10 adult cats. The central lateral nucleus received projections from the forebrain, brainstem and cerebellum. The nuclei, projected to the caudal region of the central lateral nucleus, included the dorsal division of the ventral lateral geniculate nucleus, the thalamic reticular nucleus and the deep layers of superior colliculus, primarily on the ipsilateral side. The intralaminar thalamic nucleus, the lateral hypothalamus and the reticular part of substantia nigra sent axons to terminate in the rostral region of the central lateral nucleus, with an ipsilateral predominance. The nuclei, projected to the whole length of the central lateral nucleus, were the vestibular neuclei, the reticular formation of brainstem, zona incerta, pretectal area, cells surrounding the occulomotor complex, principal sensory trigeminal, cuneatus, gracilis as well as cerebellar dentate. The vestibular nuclei and the reticular formation of brainstem were found bilateral projection, the former predominantly in contralateral, the latter mainly in ipsilateral part. Except the zona incerta, pretectal area and cells surrounding the occulomotor, the rest were labeled primarily on the contralateral side. If HRP was injected into the central lateral nucleus and spread to the ventral anterior nucleus of thalamus, a lot of HRP-positive cells were found in the entopeduncular nucleus, while the ventral tegmental nucleus of Gudden was filled with densely labeled terminals mainly on the ipsilateral side. These findings indicate that the central lateral nucleus of thalamus may be involved multiple sensory and motor functions.
ABSTRACT
The projection from the ventral posterior nucleus (VP) of the thalamus to the somatic sensory cortical area (SmI) in the rat was studied with the horseradish peroxidase (HRP) method.When injections were made into the anterior part of SmI (Brodmann 3), labeled cells were found in the ventral area of caudal VP. When injections were made into the posterior part of SmI (Brodmann 3,1), Iabeled cells were observed in the dorsal area of caudal VP. With injections located near the superior part of SmI (Brodmann 3), labeled cells were found in the lateral area of VP. When injections were made into the inferior part of SmI (Brodmann 2), labeled cells were seen in the medial area of VP.All labeled cells were observed in the injected side, indicating that the projection is uncrossed.Neurons in VP Projecting to Brodmann 2 is less than those projecting to Brodmann 3.Relationship between the quantity of labeled neurons and the amount of projection fibers was discussed.
ABSTRACT
The afferent projections to the hippocampus were studied with HRP. Thirty three per cent solution of HRP was slowly injected into the dorsal or ventral hippocampus on its right side in 25 albino rats and HRP-labelled cells were found in the following nuclei:1. On the ipsilateral side: entorhinal cortex, medial septal nucleus, supramammillary nucleus, submammillothalamic nucleus, dorsal raphe nucleus, median raphe nucleus, locus coeruleus, diagonal band and nucleus of superior colliculus.2. On the contralateral side: areas CA_3 and CA_4 of hippocampus and locus coeruleus.
ABSTRACT
WGA-HRP was injected into the dorsomedial nucleus of thalamus (DM)by means of microiontophoretical delivery in 19 rats, and into the dorsal division of anterior cingulate cortex (ACd), the prelimbic area (PL), the dorsal agranular insular area (AId) of prefrontal cortex by using microinjective system in 17 rats to observe the efferent projections of the DM.It was found that the DM projected to a large part of the prefrontal cortex including the medial precentral area (PCm), ACd, PL, AId, ventral agranular insular area (AIv), medial orbital area (MO), ventral orbital area (VO), ventrolateral orbital area (VLO), and some topographical organizations were also found. The lateral segment of DM projects to the ACd, PCm, PL, AId, AIv and VLO. The intermediate segment of DM projects to the AId and AIv. The medial segment of DM projects to the AId, PL, IL, AIv, MO and VO. Furthermore, the DM also projects to some subcortical nuclei, such as the reticular nucleus of thalamus (R), the lateral preoptic area (LPO), the lateral hypothalamic area (LHA), the caudoputamen, the nucleus accumbens and the parafascicular nucleus of thalamus. In addition, some reciprocal connections between the DM and the ACd, PCm, PL, IL, AId, R, LPO and LHA were observed.
ABSTRACT
Cytoarchitecture of the ventrolateral superficial area of the medulla was studied on normal rabbit Nissl sections.There was a superficial area of small and medium sized cells,mostly fusiform,lateral to the pyramid.In middle and upper parts of the medulla superficial cells were also found in less amount in more lateral regions. At the middle medullary level there was a band of cells about 300 ?m from the surface with medium sized ones as its most prominent elements. HRP or WGA-HRP was injected in 10 rabbits into the cervical,thoracic or lumbar spinal cord unilaterally and its connection with the ventrolateral superficial area of the medulla was traced.Labeled cells were found in all cases along the pyramid.The lateral part of the superficial area was less labeled.The medium sized cell band at the middle medulla was markedly labeled,especially in thoracic injec- tion cases.More labeled cells were found in cervical injection cases in an area ventromedial to the facial nucleus. Anterogradely labeled terminal arborizations were in general small in amount, somewhat more prominent in cervical cases. The relation between the ventrolateral superficial area and the chemosensitive area is disscussed.
ABSTRACT
37.5?m),showing light,scattered and small granules and gamma motoneurons(diameter
ABSTRACT
2?l 10% ricin were injected into the pelvic nerve of cats. After 3～5 survival days 20% HRP solution was injected into the ipsilateral lateral parabrachial nucleus, 2～3 days later the animals were perfused with paraformaldehyde and glutaraldehyde, the brain and spinal cord were removed and processed for light and electron microscopy. It was confirmed that the primary afferent terminals (degenerated) of pelvic nerve formed axo-dendritic and axo-somatic synapses with the retrograde labelled neurons projected to the lateral parabrachial nucleus which were located in the dorsal commissure nucleus (DCN), intermediolateral nucleus (IML) and lamina Ⅰ of sacral spinal cord. Hence, the secondary afferent pathway of pelvic visceral sensation, as. indicated at the ultrastructural level, might originate from DCN, IML and lamina Ⅰ of sacral spinal cord and project to the lateral parabrachial nucleus.
ABSTRACT
The cervical, thoracic, or lumbar spinal gray was injected with HRP or WGAHRP unilaterally in 18 adult rabbits and the anterograde labeling was traced in the pontine nucleus and the caudal pontine ventrolateral tegmentum.In the pontine nucleus labeled terminal arborizations were found in its caudal 1/3, distributing in the paramedian nucleus, the dorsal part of peduncular nucleus and the dorsolateral nucleus. In the ventrolateral tegmentum four small cell groups were found labeled which were temporarily denominated as VLPT_(1～4) groups. In all locations labelings were found bilaterally and no apparent somatotopical localization could be identified.The cytoarchitecture of VLPT_(1～4) was studied on Nissl sections and their relationship with Meessen and Olszewski's (M-O's) "k" and "m" groups and with pontobulbar body was discussed. VLPT_2 (corresponding to the ventral part of M-O's "k") and VLPT_3 (corresponding to a part of M-O's "m") join each other to form one group which then merges into the dorsolateral nucleus of the pontine gray. They apparently form a part of the pontobulbar body.