The Characteristics of Supramammillary Cells Projecting to the Hippocampus in Stress Response in the Rat

The hypothalamus-pituitary-adrenocortex (HPA) axis is the central mediator of the stress response. The supramammillary (SuM) region is relatively unique among the hypothalamic structures in that it sends a large, direct projection to the hippocampal formation. It has been shown that mild stress could activate the SuM cells that project to the hippocampus. However, the role of these cell populations in modulating the stress response is not known. The present study examined the effect of stress on different populations of SuM cells that project to the hippocampus by injecting the fluorescent retrograde tracer, fluorogold (FG), into the hippocampus and utilizing the immunohistochemistry of choline acetyltransferase (ChAT), corticotrophin releasing factor (CRF), serotonin (5-HT), glutamate decarboxylase (GAD), tyrosine hydroxylase (TH) and NADPH-d reactivity. Immobilization (IMO) stress (2 hr) produced an increase in the expression of ChAT-immunoreactivity, and tended to increase in CRF, 5-HT, GAD, TH-immunoreactivity and nitric oxide (NO)-reactivity in the SuM cells. Fifty-three percent of 5-HT, 31% of ChAT and 56% of CRF cells were double stained with retrograde cells from the hippocampus. By contrast, a few retrogradely labeled cells projecting to the hippocampus were immunoreactive for dopamine, gamma-aminobutyric acid (GABA) and NO. These results suggest that the SuM region contains distinct cell populations that differentially respond to stress. In addition, the findings suggest that serotonergic, cholinergic and corticotropin releasing cells projecting to the hippocampus within the SuM nucleus may play an important role in modulating stress-related behaviors.

Comparative Study of the L5 Spinal Nerve Transection Model and Sciatic Nerve Axotomy Model as a Peripheral Nerve Injury Model in Rat / 체질인류학회지

The aim of this study was to propose new more reliable peripheral nerve transection model to overcome the defect of the traditional sciatic axotomy model by specifically transecting L5 spinal nerve just after emerging from the intervertebral foramen and confining analysis area to the L5 spinal segment. The adult male Sprague-Dawley rats, weighing 300~350 g at the time of surgery, were used for the experiments. Four different experimental groups were used. 1. Sciatic nerve transection (Sc-Tx) group: transect the sciatic nerve in the popliteal fossa where it divided into the common peroneal nerve and tibial nerve. 2. L5 spinal nerve transection (L5-Tx) group: L5 spinal nerve was specifically transected. 3. Suture (Su) group: L5 spinal nerve was transected and immediately sutured. 4. Control group: the same surgical procedure with L5 spinal nerve transection group was performed except for the excision of L5 spinal nerve. To distinguish L5 motoneurons from the other level ones, the animals were received the retrograde tracer, FluoroGold into the axotomized proximal nerve stump. Serial coronal frozen sections at 40 microm thick through the L4 to L6 spinal segment was performed and the resultant total number of sections was about 180. Approximate serial 50 sections (approximately 2 mm) could be considered as the L5 segment based on the number of the fluorescent signals (above 20). L5 spinal segment could be differentiated from L4 and L6 segment based on their morphological characteristics under Cresyl violet stain. In L5-Tx group, at 2 and 4 weeks post-transection, the number of L5 spinal motoneurons was reduced by 8%. Meanwhile, Sc-Tx and Su groups showed no statistically notable changes. In this study, the authors could propose more reliable peripheral nerve axotomy model than the conventional sciatic nerve axotomy model by specifically transecting L5 spinal nerve and confining the investigating area within the L5 spinal segment.

Comparative Study of the L5 Spinal Nerve Transection Model and Sciatic Nerve Axotomy Model as a Peripheral Nerve Injury Model in Rat / 체질인류학회지

The aim of this study was to propose new more reliable peripheral nerve transection model to overcome the defect of the traditional sciatic axotomy model by specifically transecting L5 spinal nerve just after emerging from the intervertebral foramen and confining analysis area to the L5 spinal segment. The adult male Sprague-Dawley rats, weighing 300~350 g at the time of surgery, were used for the experiments. Four different experimental groups were used. 1. Sciatic nerve transection (Sc-Tx) group: transect the sciatic nerve in the popliteal fossa where it divided into the common peroneal nerve and tibial nerve. 2. L5 spinal nerve transection (L5-Tx) group: L5 spinal nerve was specifically transected. 3. Suture (Su) group: L5 spinal nerve was transected and immediately sutured. 4. Control group: the same surgical procedure with L5 spinal nerve transection group was performed except for the excision of L5 spinal nerve. To distinguish L5 motoneurons from the other level ones, the animals were received the retrograde tracer, FluoroGold into the axotomized proximal nerve stump. Serial coronal frozen sections at 40 microm thick through the L4 to L6 spinal segment was performed and the resultant total number of sections was about 180. Approximate serial 50 sections (approximately 2 mm) could be considered as the L5 segment based on the number of the fluorescent signals (above 20). L5 spinal segment could be differentiated from L4 and L6 segment based on their morphological characteristics under Cresyl violet stain. In L5-Tx group, at 2 and 4 weeks post-transection, the number of L5 spinal motoneurons was reduced by 8%. Meanwhile, Sc-Tx and Su groups showed no statistically notable changes. In this study, the authors could propose more reliable peripheral nerve axotomy model than the conventional sciatic nerve axotomy model by specifically transecting L5 spinal nerve and confining the investigating area within the L5 spinal segment.

EFFECT OF ANNEXINⅡ ON THE REPAIR OF SPINAL CORD INJURY OF THE RATS / 解剖学报

Objective In order to make further investigation of the functional meaning of Ca~(2+)dependent phospholipids binding protein AnnexinⅡ,we tested the effects of AnnexinⅡ combined with embryonic neural stem cells(NSCs) transplantion on the repair of spinal cord injury(SCI). Methods The spinal cord of the adult rats was transected completely between T_9-T_(10).AnnexinⅡ and NSCs were injected at the transected site.The lesion area of the spinal cord,growth of axon,and survival number and migration of the transplanted NSCs were measured.The survival number was shown by prelabeling the NSCs with Hoechest 33342 and the growth of axon traversing the transected area was shown by fluorogold(FG) retrograde tracing.The AnnexinⅡ injection+NSCs implantation groups were compared with groups that respectively received 1.NSCs implantation alone;2.sham-operation+NSCs implantation and 3.Vehicle injection of culture medium. Results Our results demonstrated that AnnexinⅡ treatment in vivo could significantly reduce the lesion area(P

THE PROJECTIONS FROM LAMINA Ⅱ OF MEDULLARY DORSAL HORN TO PARABRACHIAL REGION, CAUDAL VENTROLATERAL MEDULLA AND SPINAL CORD IN THE RAT / 神经解剖学杂志

After injecting retrograde tracer fiuoro-gold (FG) into the parabrachial region(PB), caudal ventrolateral medulla(CVLM) and the fourth segment of cervical spinal cord (C4), respectively, neurons in laminae I ～ Ⅱ of the medullary dorsalhorn projecting to the above mentioned brain areas were observed. PB received projections from bilateral laminae I and Ⅱ withan ipsilateral dominance; CVLM and C4 received projections from ipsilateral laminae I and Ⅱ. Neurons projecting to C4 werevery sparsely distributed in laminae I and Ⅱ of the medullary dorsal horn. The projecting neurons in outer part of lamina Ⅱwere more than those in inner part of lamina Ⅱ . Combined with immunofluorescence histochemistry for calbindin-D28k(CB) andparvalbumin(PV), it was demonstrated that a part of neurons projecting to PB or CVLM showed CB-like immunoreactivity, butnone of them exhibited PV-like immunoreactivity. There were only a few neurons in lamina Ⅱ projecting to C4 and they exhibitedneither CB- nor PV-like immunoreactivity. The present study provides further evidence for the existence of projecting neurons inlamina Ⅱ and suggests that immunostaining against CB and PV may distinguish two neuronal subpopulations in lamina Ⅱ .

Origings of Dorsal Root Ganaglion Cells Innervating Anterior and Posterior Cruciate Ligaments of the Rat Knee Joint

PURPOSE: The present study was designed to examine the distribution of dorsal root ganglion(DRG) cells innervating the anterior and posterior cruciate ligaments of the Sprague-Dawley rat knee joint. MATERIALS AND METHODS: Fluoro-gold(FG) was used to identify the distribution of DRG cells innervating the ligaments, and horseradish peroxidase(HRP) was used to measure the DRG cell size innervating the ligaments. RESULTS: Neural tracers-labelled DRG cells were found ipsilaterally only in the lumbosacra1 DRGs. FG-labelled DRG cells innervating the anterior and posterior cruciate ligaments were found from the 1st lumbar DRG to the 1st sacral DOR(L1-Sl). The majority of FG-labelled DRG cells innervating the poste-rior cruciate ligaments were located in the L4, and the majority innervating the anterior cruciate ligaments were found in the L3, The size of HRP-labelled DRG cells innervating the cruciate ligaments was below 800 micromiter (c), showing that these cells were small. CONCLUSION: This study indicates that the DRG origin of sensory nerves is different in each cruciate ligament of the knee joint. But the size and the type innervating each ligament is similar.

CONNECTIONS OF THE OVAL NUCLEUS AND ITS ADJACENT AREAS OF THE BED NUCLEI OF THE STRIA TERMINALIS IN THE RAT. AFFERENT CONNECTIONS——A FLUOROGOLD AND WGA-HRP RETROGRADE TRACT-TRACING STUDY / 解剖学报

The present experiments were designed to study the afferent connections of the oval nucleus (Ov) of the bed nuclei of the stria terminalis (BST) using fluoro-gold (FG) and WGA-HRP as retrograde tracers. After injection of FG or WGA-HRP into the Ov area of the male SpragueDawley rats, a number of retrogradely labeled neurons were observed in the piriform cortex, fundus striati, subiculum, preoptie areas, horizontal limb of the diagonal band, ventral pallidum, magnocellular preoptic area, central (Ce), medial and cortical nuclei of the amygdala. A few neurons in the midline nuclei of the thalamus. were labeled. Many labeled neurons were found in the anterior, dorsal and lateral hypothalamic areas, ventral medial, arcuate and premammillary nuclei of the hypo thalamus. In the brainstem many labeled neurons were seen in the ventral part of the midbrain central gray, dorsal raphe nucleus, pedunculopontine tegmental nucleus, ventral tegmental area, compact zone of the substantia nigra, interpeduncular nuclei, interfascicular nucleus, raphe nuclei, parabrachial nuclei, locus coeruleus, mesencephalie trigeminal nucleus, dorsal vagal complex, A_5 and A_1 cell groups.In general, the distribution patterns of the labeled neurons of both tracers were quite similar except that FG labeled neurons showed much longer processes than WGA-HRP's, and some FG labeled neurons were also found in a few contralateral structures, such as central and medial nuclei of the amygdala and the horizontal limb of the diagonal band, where no WGA-HRP labeled neurons were observed.The results of this retrograde tract-tracing study together with our previous. anterograde tract-tracing study indicate that there are reciprocal connections between the Ov and the Ce, posterior part of the lateral hypothalamus and several brainstem structures.

SPINAL PROJECTIONS TO THE PARABRACHIAL NUCLEUS IN THE RAT——HRP AND FLUOROGOLD RETROGRADE TRACT TRACING STUDY / 解剖学报

By introducing a mixture of WGA-HRP and HRP or fluorogold into the parabrachial nucleus, the cell origin of the spinoparabrachial projections in the rat have been carefully examined. The labelled neurons were found in bilateral spinal gray matter, lateral spinal nucleus and lateral cervical nucleus with contralateral predominance. They were mainly located in lamina I, lamina II, lamina IV, lamina V and lamina VII of the gray matter and also in the gray matter commissure posterior to the central canal. Comparing the distribution patterns of the projection neurons in the cervical, thoracic, lumbar and sacral segments, we did not find any distinct differences. The fact that the parabrachial nucleus receives a wide extensive projections form the spinal segments suggests that the spino-parabrachial pathways are possibly involved in the transmission of multiple sensory inputs.

THE DISTRIBUTION OF NOS-POSITIVE NEURONS IN THE PROJECTING PATHWAY TO THE SUBNUCLEUS RETICULARIS DORSALIS IN THE RAT / 解剖学报

Objective To observe the distribtuion of NOS positive neurons in the projecting pathway to the subnucleus reticularis dorsalis(SRD) in the rat. Methods We used a double staining technique combined retrograde tract tracer and NADPH d histochemistry. Results FG/NOS double labeled neurons were found in the laminae Ⅰ,Ⅹ of spinal cord,dorsal raphe nucleus(DR),linear raphe nucleus(LR),and raphe obscurus nucleus(RO).In the periaqueductal gray(PAG),there were many FG labeled or NOS labeled neurons,but no FG/NOS double labeled neurons were found.Conclusion\ NO might play a role in the pathway of afferent projections of the SRD.\;[