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1.
Estimates of the number of ganglionic neurons of superior cervical sympathetic ganglia and the number of preganglionic axons in the trunks just caudal to these ganglia were obtained from a sample of primates that included: man, chimpanzee, baboon, stump-tailed macaque, rhesus monkey, and squirrel monkey. The number of ganglionic neurons ranged from 63,625 in a squirrel monkey ganglion to 1,041,652 neurons in a human ganglion. Estimates of the number of preganglionic fibers varied between 2,285 in a cervical sympathetic trunk of a squirrel monkey and 12,008 in a human specimen. The resulting ratios of preganglionic fibers to ganglionic neurons ranged from 1:28 in a squirrel monkey ganglion to 1:196 in a human ganglion. The data reported in this study reveal considerable variation in the ratio of pre- to post-ganglionic neurons, and as was noted in regard to the number of cells in the ganglion, the ratios of ganglionic to preganglionic neurons appear to increase as a function of body size. In contrast, the number of preganglionic fibers does not increase as strikingly with body size, but varies greatly in the same species. The resulting ratio between the two orders of neurons is, therefore, less predictable than the number of ganglionic neurons in any given ganglion.  相似文献   

2.
The present study describes substance P-like immunoreactivity in the ciliary ganglia of monkey (Macaca fascicularis) and cat. About 60% of neurons in the monkey ciliary ganglion and 40% in the cat ciliary ganglion were substance P-like immunoreactive, ranging from faint to moderate staining. Substance P-like immunoreactivity was located in cell bodies, dendritic profiles and axons. In the monkey, substance P-like immunoreactive pericellular arborisations were associated with about 0.5%–3% of the ganglion cells, which were either negatively, faintly or moderately stained. An electron-microscopic study demonstrated the presence of either substance P-like immunoreactive positive or negative axon terminals synapsing or closely associated with positive dendritic profiles in both the monkey and cat ciliary ganglia. The results suggest that substance P plays an important role in the ciliary ganglion, perhaps as a modulator or transmitter.  相似文献   

3.
The present study deals with the topography of retinal ganglion cells (GCs) and spatial resolution in the smelt Hypomesus japonicus. The eyes and retinae were examined by light microscopy and computerized tomography. DAPI labelling was used to visualize cell nuclei in the ganglion cell and inner plexiform layers. Two zones of increased GC density in the nasal and temporal retina were bridged by a horizontal streak with the GC density ranging from 5600 to 8000 cells/mm2. The maximum cell density (area retinae temporalis) ranged from 9492 to 14,112 cells/mm2, and the total number of GCs varied from 286 x 103 to 326 x 103 cells in three individuals. The theoretical anatomical spatial resolution (the anatomical estimate of the upper limit of visual acuity) was minimum in the ventral periphery (smaller fish, 1.43 cpd; larger fish, 1.37 cpd) and maximum in area retinae temporalis (smaller fish, 2.83 cpd; larger fish, 2.41 cpd). The relatively high density of GCs and presence of the horizontal streak and area retinae temporalis in the H. japonicus are consistent with its highly visual behaviour. The present findings contribute to better understanding of the factors affecting the topography of retinal ganglion cells and mechanisms of visual adaptation in fish.  相似文献   

4.
S K Leong  W C Wong 《Acta anatomica》1990,138(4):281-284
The stellate and coeliac ganglia of 2 Macaque monkeys were cut serially at 1 micron thickness and analysed. Results from the analysis of 82 stellate and 60 coeliac ganglion cells in 1 monkey show that in cross-sections, the neuronal nuclei may be eccentric, centric or nearly centric and remain so throughout the longitudinal extent of the neuron. In both ganglia, the majority of neurons possess eccentric nuclei, but in the coeliac ganglion, the percentage of neurons with centric and/or nearly centric nuclei is higher (41.7%) than that in the stellate ganglion (26.3%). While 5% of neurons in the coeliac ganglion are binucleated, no binucleated neurons were found in the stellate ganglion. The somal size ranges of the stellate (10-39 microns) and the coeliac (14.5-45 microns) ganglion neurons as obtained from both monkeys are quite close. The percentage frequency distribution of the stellate ganglion neurons in monkey 1 was also quite similar to that of the coeliac ganglion neurons. It is concluded that different neuronal size is not likely to be associated with different target organs.  相似文献   

5.
6.
Abstract. Total, viable and necrotic tumour tissue, tumour cell yields, and colony forming efficiencies were measured in clone A human colon tumour xenografts as neoplasms grew from about 100 mm3 to about 6000 mm3. The volumes of the total, viable and necrotic compartments were fit using the Verhulst equation to obtain estimates of growth rates and maximal sizes of the various compartments (carrying capacities). Additionally, at four discrete tumour volumes (250, 850, 2500 and 5500 mm3), hypoxic percentages, proportions of parenchymal tumour and host cells, interstitial fluid pressures, and proliferation kinetics including measurements of apoptosis were determined. There were interesting relationships between the shapes of the curves for total, viable and necrotic tissue to some of the other endpoints measured. Specifically, the volumetric growth curves for the total and viable tumour tissue compartments were identical to a volume of approximately 1000 mm3, but diverged at larger sizes, with the viable cell compartment exhibiting a smaller carrying capacity. The shape of the growth curve for the necrotic compartment exactly mimicked that for the total volume compartment, but was delayed in time by about 21 days. Similarity in shape to that of the overall tumour volume/necrotic volume curves was also seen for the curve for the increase in interstitial fluid pressure, and for the increase in the size of the host cell compartment. In contrast, the growth of the hypoxic compartment and of the parenchymal tumour cell compartment were similar in shape to that of the viable compartment. These data indicate that these compartments are functionally linked. Marked changes in cell kinetic parameters occurred as tumour size increased from 250–5500 mm3. The labelling index and growth fractions decreased from 0.256–0.125, and 0.77–0.40 respectively, and the cell loss factor increased from 0.52–0.74. The volumetric and potential doubling times increased from 4.3–17.6 and 2.1–4.6 days respectively. The cell kinetic changes could not be clearly related to the changes in shape of either the overall tumour volume or the viable tumour volume.  相似文献   

7.
Determination of squirrel monkey prolactin by immunoassay has been hampered by the lack of antiserum specific to prolactin from this species. As an alternate method, we have investigated whether the Nb2 lymphoma bioassay could be adapted for routine measurement of the lactogenic activity of samples of squirrel monkey serum. The growth of the Nb2 cells is absolutely dependent on the presence of lactogens in the culture medium. The cells were maintained in Fisher's medium supplemented with 10% horse serum, 10% fetal calf serum (FCS), and 10?4M β-mercaptoethanol. For each assay, the cells were plated at an initial density of 1 × 105 cells/ml in 22-mm 12-well dishes in the above medium, but devoid of FCS. Serum samples were heated to 56°C for 20 minutes to abolish the unusually high cytolytic complement activity of squirrel monkey serum and were incubated for 72 hours with Nb2 cells at serial dilutions from 1/40 to 1/2,560. Growth curves were generated with pooled samples of squirrel monkey serum, and the level of lactogenic activity was estimated using a calibration growth curve generated with known concentrations of purified rhesus monkey prolactin standard. We have found that the Nb2 lymphoma bioassay provides a sensitive and adaptable means for determination of lactogenic activity in the serum of the squirrel monkey.  相似文献   

8.
In the presence of 12-O-tetradecanoylphorbol-13-acetate (TPA) or the non-TPA-type tumor promoter, palytoxin, recombinant human insulin growth factor-I (IGF-I) and insulin synergistically stimulate prostaglandin production in rat liver cells (the C-9 cell line). Combinations fo palytoxin or TPA with recombinant human IGF-I or insulin also synergistically stimulate deesterification of c ellular lipids in C-9 cells prelabelled with [3H]arachidonic acid. With both types of stimulations, prostaglandin production or deesterification, the synergistic response of the IGF-I and insulin is greater with palytoxin than with TPA. Production of prostaglandin E2 and F by squirrel monkey smooth muscle cells incubated in the presence of TPA and insulin also is greater than the sum of the effects taken independently.  相似文献   

9.
The cell proliferation kinetics of the EMT6/M/AC mouse tumour were determined at four different volumes between 1–5 mm3 and 175 mm3. The decrease in the growth rate between these volumes was mainly due to a decrease in the rate constant for cell production. A small increase in the rate constant for cell loss occurred, but this was thought to be insignificant. The cell loss factor increased from 40% at 1–5 mm3 to over 70% in the 175 mm3 tumours. An increase in the median cell cycle time, from 14-1 hr to 18-5 hr was also found between these same volumes. Results obtained for the NCTC fibrosarcoma and the R-l rhabdomyosarcoma indicate that there may be a threshold volume in these sarcomas below which little or no cell loss takes place. This was not found in the EMT6/ M/AC tumour.  相似文献   

10.
The localization and distribution of neuropeptides including neuropeptide Y (NPY), [Met5]enkephalin-Arg6-Gly7-Leu8 (MEAGL), vasoactive intestinal polypeptide (VIP), calcitonin gene-related peptide (CGRP), substance P and somatostatin (SOM) were analyzed in the stellate ganglion of the pig by use of the indirect immunofluorescence technique. NPY, MEAGL, SOM, VIP and CGRP immunoreactivities were found to exist in subpopulations of neuronal cell bodies of the stellate ganglion. A population of the small intensely fluorescent (SIF) cells showed MEAGL immunoreactivity. In addition, the presence of NPY-, MEAGL-, CGRP-, SP-, SOM- and VIP-immunoreactive nerve fibers and axonal varicosities were observed in the stellate ganglion. The localization and pattern of distribution of these peptides in the porcine stellate ganglion were compared with studies carried out on stellate ganglia of other mammalian species.  相似文献   

11.
Primary cultures containing ≥99% neurons, ≥99% non-neuronal cells (glia), or both cell types were prepared from the sympathetic ganglia of 12-day chick embryos. Levels of cyclic AMP in the non-neuronal cells (~14 pmol/mg protein) were approximately 3-fold higher than levels in the neurons (~4 pmol/mg protein). Mixed cultures had concentrations of cyclic AMP which fell between the values measured for pure neuronal and pure non-neuronal cultures. The measured cyclic AMP values of mixed cultures were indistinguishable from values predicted by summing the expected contributions of the neurons and non-neuronal cells. Thus, contact between the neurons and non-neuronal cells in these mixed cultures did not appear to alter the level of cyclic AMP in either cell type. Neuronal-glial interactions, such as the specific neuronal stimulation of non-neuronal cell proliferation, occurred independently of any changes in the level of cyclic AMP in the mixed cultures. Cell density was varied in both pure and mixed cultures, and both cyclic AMP concentrations and amounts of [3H]thymidine incorporation into DNA were measured. The cyclic AMP content of the non-neuronal cells varied inversely with cell density. [3H]Thymidine incorporation was independent of cell density in both neuronal and non-neuronal cultures. Parallel density-dependent decreases in cyclic AMP concentration and [3H]thymidine incorporation were observed in mixed cultures as cell density was increased. The data suggest that there is no relationship between changes in rate of non-neuronal cell proliferation and cyclic AMP levels in these cultures.  相似文献   

12.
Ciliary neuronotrophic factor (CNTF) requirements for neuronal survival in the intact ciliary ganglion (CG) have been investigated in organ culture. Exogenous CNTF was not essential for neuronal survival until embryonic Day 8. Three-day cultures from 5-day ganglia were similar with or without CNTF, showing numerous neurons and extensive neuritic development. In 3-day cultures from 8-day-old ganglia, however, no neurons survived without CNTF, and the ganglia contained only nonneuronal cells and cell debris. Similar ganglia cultured with CNTF contained many neurons, surrounded by nonneuronal cells, and abundant neuritic processes. Morphologic maturation of the neurons was less advanced in CNTF-supported ganglia than in their in vivo counterparts.  相似文献   

13.
Migration of neurons over long distances occurs during the development of the adult central nervous system of the sphinx moth Manduca sexta, and the turnip moth Agrotis segetum. From each of the suboesophageal and three thoracic ganglia, bilaterally-paired clusters of immature neurons and associated glial cells migrate posteriorly along the interganglionic connectives, to enter the next posterior ganglion. The first sign of migration is observed at the onset of metamorphosis, when posterio-lateral cell clusters gradually separate from the cortex of neuronal cell bodies and enter the connectives. Cell clusters migrate posteriorly along the connective to reach the next ganglion over the first three days (approximately 15%) of pupal development. During migration, each cell cluster is completely enveloped by a single giant glial cell spanning the entire length of the connective between two adjacent ganglia. Intracellular cobalt staining reveals that each migrating neuron has an ovoid cell body and an extremely long leading process which extends as far as the next posterior ganglion; this is not a common morphology for migrating neurons that have been described in vertebrates. Once the cells arrive at the anterior cortex of the next ganglion, they rapidly intermingle with the surrounding neurons and so we were unable to determine the fate of the migrating neurons at their final location.  相似文献   

14.
This study describes the post-embryonic growth of the terminal ganglion in Acheta domesticus in terms of volume and cell number. All measurements were made at the beginning of each instar from hatching until the final moult on animals reared under controlled conditions. The terminal ganglion increases about 40-fold in volume from 2 × 106 μ3 in the first instar to 85 × 106 μ3 in the adult. A double logarithmic plot of ganglion volume against body weight shows that the ganglion volume is a function of body weight to the 0.56 power. Initially the neuropile grows at a greater rate than the cortex; in later stages they increase at the same rate. Increase in cell number was determined from serial sections. The total number of cells, based on corrected nuclear counts, increases from 3,400 to 20,000. There is little or no increase in the number of neurons. There are approximately 2,000 association neurons and 100 motor neurons in all stages. The number of glial cells increase from 1,000 to 17,000. Their multiplication rate appears to be related to the increase in neuron volume. Despite the increase in glial cell number, increase in cell volume is primarily responsible for the increase in total volume of the ganglion.  相似文献   

15.

Background

The afferent projections of the striatum (caudate nucleus and putamen) are segregated in three territories: associative, sensorimotor and limbic. Striatal interneurons are in part responsible for the integration of these different types of information. Among them, GABAergic interneurons are the most abundant, and can be sorted in three populations according to their content in the calcium binding proteins calretinin (CR), parvalbumin (PV) and calbindin (CB). Conversely, striatal dopaminergic cells (whose role as interneurons is still unclear) are scarce. This study aims to analyze the interneuron distribution in the striatal functional territories, as well as their organization regarding to the striosomal compartment.

Methodology/Principal Findings

We used immunohistochemical methods to visualize CR, PV, CB and tyrosine hydroxylase (TH) positive striatal neurons. The interneuronal distribution was assessed by stereological methods applied to every striatal functional territory. Considering the four cell groups altogether, their density was higher in the associative (2120±91 cells/mm3) than in the sensorimotor (959±47 cells/mm3) or limbic (633±119 cells/mm3) territories. CB- and TH-immunoreactive(-ir) cells were distributed rather homogeneously in the three striatal territories. However, the density of CR and PV interneurons were more abundant in the associative and sensorimotor striatum, respectively. Regarding to their compartmental organization, CR-ir interneurons were frequently found in the border between compartments in the associative and sensorimotor territories, and CB-ir interneurons abounded at the striosome/matrix border in the sensorimotor domain.

Conclusions/Significance

The present study demonstrates that the architecture of the human striatum in terms of its interneuron composition varies in its three functional territories. Furthermore, our data highlight the importance of CR-ir striatal interneurons in the integration of associative information, and the selective role of PV-ir interneurons in the motor territory. On the other hand, the low density of dopaminergic cells casts doubts about their role in the normal human striatum.  相似文献   

16.
Unlike all other New World (platyrrine) monkeys, both male and female howler monkeys (Alouatta sp.) are obligatory trichromats. In all other platyrrines, only females can be trichromats, while males are always dichromats, as determined by multiple behavioral, electrophysiological, and genetic studies. In addition to obligatory trichromacy, Alouatta has an unusual fovea, with substantially higher peak cone density in the foveal pit than every other diurnal anthropoid monkey (both platyrrhines and catarrhines) and great ape yet examined, including humans. In addition to documenting the general organization of the retinal ganglion cell layer in Alouatta, the distribution of cones is compared to retinal ganglion cells, to explore possible relationships between their atypical trichromacy and foveal specialization. The number and distribution of retinal ganglion cells and displaced amacrine cells were determined in six flat-mounted retinas from five Alouatta caraya. Ganglion cell density peaked at 0.5 mm between the fovea and optic nerve head, reaching 40,700–45,200 cells/mm2. Displaced amacrine cell density distribution peaked between 0.5–1.75 mm from the fovea, reaching mean values between 2,050–3,100 cells/mm2. The mean number of ganglion cells was 1,133,000±79,000 cells and the mean number of displaced amacrine cells was 537,000±61,800 cells, in retinas of mean area 641±62 mm2. Ganglion cell and displaced amacrine cell density distribution in the Alouatta retina was consistent with that observed among several species of diurnal Anthropoidea, both platyrrhines and catarrhines. The principal alteration in the Alouatta retina appears not to be in the number of any retinal cell class, but rather a marked gradient in cone density within the fovea, which could potentially support high chromatic acuity in a restricted central region.  相似文献   

17.

Purpose

To investigate anterograde degenerative changes along the visual pathway in a rat model of optic nerve axotomy.

Methods

Optic nerve transection was performed in adult Sprague-Dawley rats. Animals were sacrificed at regular time intervals and tissues harvested. Immunoblotting followed by densitometric analysis was used to determine the phosphorylation profile of Akt in the dorsal lateral geniculate nucleus (dLGN) and the primary visual cortex (V1). The neuronal cell size and cell density were measured in the dLGN and the V1 using Nissl staining. The prevalence of apoptosis was characterized by terminal deoxynucleotidyl-transferase-mediated biotin-dUTP nick end labelling (TUNEL) histochemistry. Caspase-3 antibodies were also used to identify apoptotic cells. Neurons and astrocytes were detected using NeuN and glial fibrillary acidic protein (GFAP), respectively.

Results

An early and sustained loss of Akt phosphorylation was observed after optic nerve transection in both dLGN and V1. At week one, a decrease in the neuronal cell size (50.5±4.9 vs 60.3±5.0 µm2, P = 0.042) and an increase of TUNEL positive cells (7.9±0.6 vs 1.4±0.5 ×102 cells/mm2, P<0.001) were evident in the dLGN but not in V1. A significant decline in neuronal cell number (14.5±0.1 vs 17.4±1.3 ×102 cells/mm2, P = 0.048), cell size (42.5±4.3 vs 62.1±4.7 µm2, P = 0.001) and an increase in apoptotic cells (5.6±0.5 vs 2.0±0.4 ×102 cells/mm2, P<0.001) appeared in V1 initially at one month post-transection. The changes in the visual pathway continued through two months. Both neuronal cells and GFAP-positive glial cells were affected in this anterograde degeneration along the visual pathway.

Conclusions

Anterograde degeneration along the visual pathway takes place in target relay (LGN) and visual cortex following the optic nerve injury. Apoptosis was observed in both neural and adjacent glial cells. Reduction of Akt phosphorylation preceded cellular and apoptotic changes.  相似文献   

18.
Squirrel monkeys are among a diverse group of New World primates that demonstrate unusually high levels of circulating corticosteroids and glucocorticoid receptor (GR) insensitivity. Recent evidence suggests that overexpression of an immunophilin impairs dexamethasone binding to GR in the Bolivian squirrel monkey (Saimiri boliviensis). Here we describe the cloning, expression, and functional characterization of GR from the closely related Guyanese squirrel monkey (S. sciureus). The cloned Guyanese squirrel monkey GR (gsmGR) cDNA closely resembles human GR (hGR) cDNA, and yields a high affinity dexamethasone binding receptor when expressed in COS-1 cells. Transactivation analysis of hGR and gsmGR expressed in CV-1 cells and cultured squirrel monkey kidney (SMK) cells indicates that: (1) SMK cells elaborate a functional high activity GR from human GR cDNA; (2) gsmGR is an order of magnitude less efficient than hGR at transactivation in CV-1 and SMK cells; and (3) maximal transactivation by gsmGR is attenuated in both cell lines. Glucocorticoid resistance in S. sciureus is at least partly attributable to a naturally occurring mutation in the GR gene that results in impaired GR transactivation.  相似文献   

19.
The distribution and size of ganglion cells in the retina of two tucuxi were investigated. Retinal cell size varied from 10 to 50 μm with a polymodal size distribution; major groups were seen with sizes of 8-20, 21-35, and more than 35 μm. Ganglion cells concentrated at two spots of the highest density in the nasal and temporal quadrants, about 10 mm (60′) from the optic disk. The mean peak cell density in both spots was 188-198 cells/mm2. With a posterior nodal distance of 9.5-10 mm (underwater), the density at those two spots corresponded to 5.4-5.7 cells/deg2, which provides a retinal resolution of 25′-26′ (1.16-1.19 cycle/deg) in water and 33′-34′ (0.9 cycle/deg) in air.  相似文献   

20.
The caudal ganglion of the leech, which provides sensory and motor innervation to the posterior sucker, represents the fusion of seven embryonic segmental ganglia. Although fused, each of the seven contributing ganglia (“subganglia”) of the caudal ganglion can be distinguished morphologically and functionally. The roots from each subganglion carry the axons of mechanoreceptors homologous to “touch” cells found in the segmental ganglia and the subesophageal compound ganglion. The receptive fields supplied by the touch cells of the caudal ganglion are uniquely arranged and reveal the modified segmentation of the circular posterior sucker. Extensive overlap of sensory innervation occurs between adjacent segments of the sucker, beyond the overlap characteristic of the homologous cells of body segments. It thus appears that the touch receptors of the caudal ganglion are less restricted than receptors of the segmental ganglia with regard to their territories of innervation. The caudal ganglion has additional unique properties that establish it as a distinct integrative center of the leech CNS.  相似文献   

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