bluuebunny/crossref_metadata_2025_split huggingface dataset:
Distribution of phenylethanolamine N‐methyltransferase cell bodies, axons, and terminals in monkey brainstem: An immunohistochemical mapping study
Authors: Carlton Susan M. , Honda Christopher N. , Denoroy Luc 
Published: January 2005

AbstractAdrenaline (epinephrine) is an important candidate transmitter in descending spinal control systems. To date intrinsic spinal adrenergic neurons have not been reported; thus adrenergic input is presumably derived from brainstem sites. In this regard, the localization of adrenergic neurons in the brainstem is an important consideration. Maps of adrenergic cell bodies and to a lesser axons and terminal fields have been made in various species, but not in monkeys. Thus, the present study concerns the organization of adrenergic systems in the brainstem of a monkey (Macaca fascicularis) immunohistochemically mapped by means of an antibody to the enzyme phenylethanolamine N‐methyltransferase (PNMT). PNMT‐immunostained cell bodies are distributed throughout the medulla in two principal locations. One concentration of labeled cells is in the dorsomedial medulla and includes the nucleus of the solitary tract (NTS), the dorsal motor nucleus of the vagus (X), and an area ventral to X in a region of the reticular formation (RF) known as the central nucleus dorsalis (CnD) of the medulla. A few scattered cells are observed in the periventricular gray just ventral to the IVth ventricle and on midline in the raphe. The second major concentration of PNMT‐immunostained cells is located in the ventrolateral RF, lateral and dorsolateral to the inferior olive (IO), including some cells in the rostral part of the lateral reticular nucleus (LRN). Terminal fields are located in the NTS, X, area postrema (AP), and the floor of the IVth ventricle in the medulla and pons. A light terminal field is also observed in the raphe, particularly raphe pallidus (RP). A heavy terminal field is present in locus coeruleus (LC). Fibers labeled for PNMT form two major fiber tracts. One is in the dorsomedial RF extending as a well‐organized bundle through the medulla, pons, and midbrain. A second tract is located on the ventrolateral edge of the medulla and caudal pons. Fibers in this tract appear to descend to the spinal cord. A comparison with maps of other catecholamine neurons in primates is discussed, confirming that the distribution of the adrenergic system in monkeys is similar to that described in the human.
Development of microglia in the albino rabbit retina
Authors: Ashwell Ken 
Published: January 2005

AbstractIn this study the development of ameboid microglia and resting microglia in the retina of the albino rabbit has been examined by means of a lectin derived from Griffonia simplicifolia. Ameboid microglia are present in the retina as early as E12, when the optic fissure is in the process of closure, and appear to be concentrated initially at the vitreal surface. At E14 many ameboid microglia can be seen to extend processes to the ventricular surface of the cytoblast layer, but in subsequent ages these cells are rare and ameboid microglia are largely confined to the ganglion cell layer, inner plexiform layer, and occasionally the developing inner nuclear layer. By adult life, mature (or resting) microglia are confined to the inner plexiform and ganglion cell layers. Numbers of microglia increase steadily throughout fetal life from a mean of 400 at E14, the earliest age quantified, to a peak of 28,600 at E30. There is a small postnatal drop in numbers to 17,150 at P9. Microglia could only be labelled faintly in animals older than P11, but analysis of two adult (P130) retinas with adequate labelling suggested that numbers rise to a value of about 23,800 at this age. Ameboid microglia thus appear in the retina 11 days prior to the onset of axon loss in the optic nerve (about E23) and 14 days prior to the beginning of the period of reduction of retinal ganglion cell numbers (about E26). The present findings indicate that while some microglial precursors may enter the retina in response to debris generated during the natural retinal ganglion cell death period, most enter the retina well before this period. Also, microglia present a uniform density distribution with apparently regular spacing as early as E16, so the uniform regular distribution cannot simply be the consequence of regularly distributed pyknotic figures as previously suggested.
Vasopressin and oxytocin systems in the brain and upper spinal cord of Macaca fascicularis
Authors: Caffé A. R. , Van Ryen P. C. , Van Der Woude T. P. , Van Leeuwen F. W. 
Published: January 2005

AbstractThis paper describes the vasopressin (VP) and oxytocin (OXT) immunoreactive structures in the brain and upper spinal cord of the adult male and female Macaca fascicularis.Immunocytochemistry following intraventricular application of colchicine displayed VP neurons in the diagonal band of Broca (DBB), bed nucleus of the stria terminalis (BST), medial amygdaloid nucleus, dorsomedial hypothalamic nucleus, area of the locus coeruleus (LC), solitary tract nuclei (NTS), and the dorsal horn of the cervical spinal cord in addition to those known to exist in the paraventricular, supraoptic, and suprachiasmatic hypothalamic nuclei. Furthermore, a dense accumulation of VP fibers was observed in areas such as the DBB, medial septum, BST, amygdala, hippocampus, ventral tegmental area, periaquaductal gray, dorsal and ventral raphe, area of Forel, LC region, parabrachial nuclei, and NTS. The lateral septum and lateral habenula displayed no and very few VP fibers, respectively.No extrahypothalamic OXT neurons were found in the brain of this macaque monkey. Dense concentrations of OXT fibers were demonstrated in the amygdala, NTS and marginal layer of the cervical spinal cord.No sexual dimorphism was found in this primate VP or OXT system.The results show a distribution of the central VP and OXT systems in this primate which is quite different from that in the rat. However, in various aspects it agrees with current data on the VP and OXT systems of the human brain. The present results suggest, therefore, that this monkey might serve as a better model for the human VP system than the rat.
Alterations in catecholamine neurons of the locus coeruleus in senile dementia of the Alzheimer type and in Parkinson's disease with and without dementia and depression
Authors: Chan‐Palay V. , Asan E. 
Published: January 2005

AbstractThe present study provides qualitative and quantitative investigations of the norepinephrine (NE) neurons in the locus coeruleus (LC) in two neurodegenerative disorders, the senile dementia of the Alzheimer type (SDAT) and Parkinson's disease (PD). The group of PD subjects was subdivided into cases without dementia (P − D), cases with dementia, L‐dopa responsive (P + D), and cases with fulminant dementia whose motor disorder symptoms were L‐dopa nonresponsive (P + D/L‐dopa non‐responsive). NE neurons were demonstrated by immunocytochemistry against tyrosine hydroxylase (TH). Quantitations of neuronal parameters and cell numbers and three‐dimensional reconstructions of the LC were carried out with a computer‐assisted system.In SDAT cases, the rostrocaudal LC length (13 ± 2.2 mm) is shorter than in controls (14.9 ± 1.4 mm). The four basic LC neuron classes found in the normal human brain (large multipolar, large “bipolar,” small multipolar, and small “bipolar” neurons; Chan‐Palay and Asan: J. Comp. Neurol. This issue) are recognizable, but many cell somata are swollen and misshapen with foreshortened, thick, and less branched dendrites. LC neuron numbers are reduced (between − 3.5% and −87.5%). Neuron loss is greatest in the rostral part, less in the middle, and least in the caudal part.In PD cases, the rostrocaudal length (12.4 ± 1.5 mm) is shorter than in SDAT and controls. The neuronal morphology is more severely altered than in SDAT. The basic neuron classes are hardly distinguishable. Most cell bodies are swollen; they frequently contain Lewy bodies; and the dendrites are short and thin with absent or reduced arborizations. Neuron numbers are more reduced than in SDAT (between − 26.4% and −94.4%). Alterations are as severe caudally as rostrally in P − D, and P+D/L‐dopa nonresponsive cases. P+D cases are more severely affected rostrally. The presence of depression in SDAT and Parkinson's patients is accompanied by the greatest loss of LC neurons. On the basis of morphological alterations of the TH‐immunoreactive neurons, and the degree and topographical distribution of neuron loss, a differentiation is possible between the LC in normal brain and that in SDAT and PD for diagnostic purposes.
Posterior parietal cortex in rhesus monkey: II. Evidence for segregated corticocortical networks linking sensory and limbic areas with the frontal lobe
Authors: Cavada Carmen , Goldman‐Rakic Patricia S. 
Published: January 2005

AbstractWe have examined the circuitry connecting the posterior parietal cortex with the frontal lobe of rhesus monkeys. HRP‐WGA and tritiated amino acids were injected into subdivisions 7m, 7a, 7b, and 7ip of the posterior parietal cortex, and anterograde and retrograde label was recorded within the frontal motor and association cortices. Our main finding is that each subdivision of parietal cortex is connected with a unique set of frontal areas. Thus, area 7m, on the medial parietal surface, is interconnected with the dorsal premotor cortex and the supplementary motor area, including the supplementary eye field. Within the prefrontal cortex, area 7m's connections are with the rostral sector of the frontal eye field (FEF), the dorsal bank of the principal sulcus, and the anterior bank of the inferior arcuate sulcus (Walker's area 45). In contrast, area 7a, on the posterior parietal convexity, is not linked with premotor regions but is heavily interconnected with the rostral FEF in the anterior bank of the superior arcuate sulcus, the dorsolateral prefrontal convexity, the rostral orbitofrontal cortex, area 45, and the fundus and adjacent cortex of the dorsal and ventral banks of the principal sulcus. Area 7b, in the anterior part of the posterior parietal lobule, is interconnected with still a different set of frontal areas, which include the ventral premotor cortex and supplementary motor area, area 45, and the external part of the ventral bank of the principal sulcus. The prominent connections of area 7ip, in the posterior bank of the intraparietal sulcus, are with the supplementary eye field and restricted portions of the ventral premotor cortex, with a wide area of the FEF that includes both its rostral and caudal sectors, and with area 45. All frontoparietal connections are reciprocal, and although they are most prominent within a hemisphere, notable interhemispheric connections are also present.These findings provide a basis for a parcellation of the classically considered association cortex of the frontal lobe, particularly the cortex of the principal sulcus, into sectors defined by their specific connections with the posterior parietal subdivisions. Moreover, the present findings, together with those of a companion study (Cavada and Goldman‐Rakic): J. Comp. Neurol. This issue have allowed us to establish multiple linkages between frontal areas and specific limbic and sensory cortices through the posterior parietal cortex. The net‐works thus defined may form part of the neural substrate of parallel distrib‐uted processing in the cerebral cortex.
Anterograde tracing of the rat olivocerebellar system with phaseolus vulgaris leucoagglutinin (PHA‐L). Demonstration of climbing fiber collateral innervation of the cerebellar nuclei
Authors: van der Want J. J. L. , Wiklund L. , Guegan M. , Ruigrok T. , Voogd J. 
Published: January 2005

AbstractThe olivocerebellar climbing fiber system was investigated in the rat with anterograde Phaseclus vulgaris leucoagglutinin (PHA‐L) tracing. The specific objective of the study was to find morphological evidence of climbing fiber collaterals innervating the cerebellar nuclei.Small iontophoretic injections of PHA‐L were placed in different parts of the inferior olivary complex, and labelled olivocerebellar fibers could be traced to their termination as climbing fibers in sagittal zones of the contralateral cerebellar cortex. Reaching the cerebellum via the restiform body, the labelled olivocerebellar axons entered the deep cerebellar white matter anterior to the cerebellar nuclei. Most of these thicker, nonterminal axons continued dorsally around the nuclei, but some ran through them. Bundles of fibers could be followed into the folial white matter toward their cortical zones of termination.Depending on which part of the olivary complex that was injected with PHA‐L, labelled axons were seen to converge on different regions of the cerebellar nuclei, where dense plexuses of thin varicose terminal fibers appeared. Quantitative estimates of the innervation ranged from 1.7 to 4.3 million boutons per mm3 in the fastigial (FN), interposed, and main parts of the lateral cerebellar (LCN) nuclei, whereas the parvicellular portion of LCN demonstrated 15–20 million varicosities per mm3. Frequently, thicker olivocerebellar axons, which seemed directed toward the cerebellar cortex, were seen to send a fine collateral branch toward these areas of nuclear innervation.As controls, PHA‐L was injected into the degenerated olivary complex of 3‐acetylpyridine‐treated rats. Neither cortical climbing fiber terminals nor nerve terminal plexuses in the nuclei appeared in these experiments. In cases with injection sites extending into the reticular formation, substantial mossy fiber labelling was present bilaterally in the cortex, but the cerebellar nuclei were devoid of labelled innervation or demonstrated only a few larger diameter fibers.The projection of the inferior olivary complex to the cerebellar nuclei was strictly topographically organized and agreed in principle with the organization described in the cat by Groenewegen et al. ('79). The caudal medial accessory olive (MAO) projected to FN, the rostral MAO to the posterior interposed nucleus (NIP), the rostral part of the dorsal accessory olive (DAO) to the anterior interposed nucleus (NIA), and the principal olive (PO) to LCN. Smaller injections into olivary subnuclei resulted in labelled innervation in restricted sectors of individual cerebellar nuclei, suggesting the existence of a more detailed topographical organization.
Glutamate and aspartate immunoreactivity in corticospinal neurons of rats
Authors: Giuffrida R. , Rustioni A. 
Published: January 2005

AbstractA combination of retrograde tracers and immunostaining was employed to test whether corticospinal tract (CST) neurons in rats may use amino acid excitatory neurotransmitters. CST neurons were identified following injections of either Diamidino Yellow (DY) or colloidal gold‐labeled enzymatically inactive horseradish peroxidase conjugated to wheat germ agglutinin (WGAapoHRP‐Au) in the spinal cord. As retrograde tracers, the two substances seemed to be equally effective, but WGAapoHRP‐Au was better suited than DY as a tracer to use in combination with immunocytochemistry. Sections through the primary sensorimotor cortex, which contained the bulk of identified CST neurons, and the secondary somatosensory cortex were processed with antisera raised in rabbits against glutamate (Glu) or aspartate (Asp) conjugated by glutaraldehyde to hemocyanin. In rats with DY injections, about 60–75% of the CST neurons were Glu‐immunopositive, with higher ratios in SI and MI than in SII. Similar results were obtained in all areas examined from the rats with injections of WGAapoHRP‐Au. Only sections from rats with injections of WGAapoHRP‐Au were processed for Asp immunostaining. In this material, between 65 and 75% of the CST neurons were Asp‐immunopositive, with a slightly higher ratio in SI and MI than in SII.The possibility that these results might reflect limited penetration of the antiserum and/or staining of the same population of CST neurons by either antiserum was addressed in sections processed with both the Glu and Asp antisera. In sections incubated in a mixture of the two antisera, the percentage of immunostained CST neurons was higher, about 90%, than in sections processed for only one of the two antisera. Furthermore, in rats in which Glu and Asp antibodies were visualized by two distinguishable immunostainings, four populations of CST neurons were identifiable: (1) neurons only immunopositive for Glu, (2) neurons only immunopositive for Asp, (3) neurons likely to be stained by both, and (4) neurons immunonegative for both antisera. Twenty‐five to 30% of CST neurons were positive for only one antiserum, and about 50% were positive for both. No preferential distribution was evident for any one of these populations of neurons. However, perikaryal cross‐sectional areas were larger for the double‐stained than for the single‐stained CST neurons.Glutamergic and aspartergic transmission in CST neurons has been proposed in several publications in which methods other than immunocytochemistry were employed. While the present observations support previous results and conclusions, it remains to be demonstrated conclusively that these amino acids, and not di‐ or oligopeptides, possibly recognized by the same antisera raised against Glu and Asp, are the natural transmitters in CST neurons.
Spino‐olivary termination on spines in cat medial accessory olive
Authors: Molinari Helen H. , Starr Kathy A. 
Published: January 2005

AbstractThree functional regions of the inferior olive, the caudal medial accessory olive (cMAO) and the caudal and rostral dorsal accessory olive (DAO) receive input from the spinal cord. The present study determined how spinal inputs to cMAO interact with olivary neurons. These inputs were labeled by injections in cat lumbosacral of wheat germ agglutinin conjugated to horseradish peroxidase. The tracer was visualized with tetramethylbenzidine. The morphology of the labeled spino‐olivary terminals and the relationship between these terminals and postsynaptic elements were determined.Spino‐olivary terminals in cMAO displayed the morphological characteristics classically associated with excitatory synapses. Almost three quarters synapsed on spines, most of which contacted other spines, forming spine clusters. The majority of postsynaptic spines also received convergent input from apparently excitatory, nonlumbosacral afferents. This postsynaptic organization provides several possible benefits for the putative role of cMAO in the control of posture.An earlier study demonstrated that in DAO, almost three quarters of lumbosacral, spino‐olivary terminals synapse on dendrites (Molinari: Neuroscience 27:425–435, 1988). Thus, lumbosacral afferents appear to differ fundamentally in the way in which they interact with neurons in cMAO and DAO. These results suggest that the way information is processed may be as important in determining the functional differences between olivary regions as what information is received.
Metabolic anatomy of brain: A comparison of regional capillary density, glucose metabolism, and enzyme activities
Authors: Borowsky Iris Wagman , Collins Robert C. 
Published: January 2005

AbstractRegional variations in capillary density, glucose utilization rate, and activities of the glycolytic enzyme lactate dehydrogenase and the mitochondrial enzyme cytochrome oxidase were compared in the rat brain. The distributions of capillaries and enzymes were studied by means of histochemical staining techniques, and glucose metabolism was measured by means of [14C]2‐deoxyglucose autoradiography. Analysis of 18 gray and five white matter regions revealed a positive correlation between capillary density and glucose utilization rate. A negative correlation was found between capillary density and lactate dehydrogenase among gray matter structures. Analysis of capillaries and enzymes was also performed within laminated histological fields: hippocampus, olfactory bulb, and olfactory cortex. In general, this revealed reciprocal patterns of staining for lactate dehydrogenase and cytochrome oxidase. Capillary density paralleled cytochrome oxidase activity. The zones of intense staining for lactate dehydrogenase and cytochrome oxidase corresponded to the synaptic terminal fields of different input pathways. These findings demonstrate distinct distributions of a glycolytic and an oxidative enzyme within the brain which are at least partly associated with pathway specificity.
Compartment‐specific changes in the density of choline and dopamine uptake sites and muscarinic and dopaminergic receptors during the development of the baboon striatum: A quantitative receptor autoradiographic study
Authors: Lowenstein P. R. , Slesinger P. A. , Singer H. S. , Walker L. C. , Casanova M. F. , Raskin L. S. , Price D. L. , Coyle J. T. 
Published: January 2005

AbstractIn the fetal and young primate neostriatum, cholinergic and dopaminergic markers show patches of high density surrounded by a lower‐density matrix. In the adult, the same markers display the opposite pattern, a lower density in striosomes, surrounded by a higher‐density matrix. In order to understand the developmental sequences leading to the adult compartmental organization of the primate neostriatum, a quantitative technique was used to study the ontogeny of pre‐ and postsynaptic components of cholinergic and dopaminergic neurons in baboon caudate nucleus and putamen. The development of specific uptake mechanisms for choline and dopamine and receptors was studied by means of quantitative autoradiography of the specific binding of [3H]‐hemicholinium‐3 ([3H]‐HC3) and [3H]‐mazindol ([3H]‐MAZ) to the choline and dopamine uptake systems, respectively. [3H]‐pirenzepine ([3H]‐PIR) was used to label M1 muscarinic receptors and [3H]‐spiroperidol ([3H]‐SPI) was used to label striatal dopamine D2 receptors. Serial sections were used for each ligand to determine the precise anatomical relationships between the binding patterns of the different markers. Our aim was to determine whether the adult striosomal distribution of the binding sites studied was due to (1) a selective decrease in patch/striosomal binding density or (2) a selective increase in matrix binding density. Our studies show that a postnatal decrease in the density of [3H]‐HC3 sites in the patch/striosomes and an increase in the matrix density of [3H]‐MAZ sites are the primary, but not the sole, changes in the compartmental distribution of these sites leading to the adult striosomal organization of the striatal cholinergic and dopaminergic innervation. D2 receptors follow the general developmental pattern of [3H]‐MAZ and [3H]‐HC3, changing their density of distribution in both compartments during the developmental period examined. In addition, M1 muscarinic receptors already display their adult pattern in the newborn baboon striatum, and therefore represent one of the first neurochemical markers to adopt its mature organization.