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41.
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
42.
Discharge patterns of chicken cochlear ganglion neurons following kanamycin-induced hair cell loss and regeneration 总被引:2,自引:0,他引:2
R. J. Salvi S. S. Saunders E. Hashino L. Chen 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1994,174(3):351-369
Hair cells in the basal, high frequency region (>1100 Hz) of the chicken cochlea were destroyed with kanamycin (400 mg/kg/d × 10 d) and allowed to regenerate. Afterwards, single unit recordings were made from cochlear ganglion neurons at various times post-treatment. During the first few weeks post-treatment, only neurons with low characteristic frequencies (<1100 Hz) responded to sound. Despite the fact that the low frequency region of the cochlea was not destroyed, neurons with low characteristic frequencies had elevated thresholds, abnormally broad U-shaped or W-shaped tuning curves and low spontaneous discharge rates. At 2 days post-treatment, the spontaneous discharge rates of some acoustically unresponsive units fluctuated in a rhythmical manner. As recovery time increased, thresholds decreased, tuning curves narrowed and developed a symmetrical V-shape, spontaneous rate increased and neurons with higher characteristic frequencies began to respond to sound. In addition, the proportion of interspike interval histograms with regularly spaced peaks increased. These improvements progressed along a low-to-high characteristic frequency gradient. By 10–20 weeks post-treatment, the thresholds and tuning curves of neurons with characteristic frequencies below 2000 Hz were within normal limits; however, the spontaneous discharge rates of the neurons were still significantly lower than those from normal animals.Abbreviations KM
kanamycin
- BrdU
bromodeoxyuridine
- CF
characteristic frequency
- CAP
compound action potential
- ISI
interspike interval 相似文献
43.
Ralph A. Nixon Susan E. Lewis Marc Mercken Ram K. Sihag 《Neurochemical research》1994,19(11):1445-1453
Newly synthesized neurofilament proteins become highly phosphorylated within axons. Within 2 days after intravitreously injecting normal adult mice with [32P]orthophosphate, we observed that neurofilaments along the entire length of optic axons were radiolabeled by a soluble32P-carrier that was axonally transported faster than neurofilaments.32P-incorporation into neurofilament proteins synthesized at the time of injection was comparatively low and minimally influenced the labeling pattern along axons.32P-incorporation into axonal neurofilaments was considerably higher in the middle region of the optic axons. This characteristic non-uniform distribution of radiolabel remained nearly unchanged for at least 22 days. During this interval, less than 10% of the total32P-labeled neurofilaments redistributed from the optic nerve to the optic tract. By contrast, newly synthesized neurofilaments were selectively pulse-labeled in ganglion cell bodies by intravitreous injection of [35S]methionine and about 60% of this pool translocated by slow axoplasmic transport to the optic tract during the same time interval. These findings indicate that the steady-state or resident pool of neurofilaments in axons is not identical to the newly synthesized neurofilament pool, the major portion of which moves at the slowest rate of axoplasmic transport. Taken together with earlier studies, these results support the idea that, depending in part on their phosphorylation state, transported neurofilaments can interact for short or very long periods with a stationary but dynamic neurofilament lattice in axons.Special issue dedicated to Dr. Sidney Ochs. 相似文献
44.
InhibitionofAcrosomalEnzymesbyGossypolIsRelatedtoItsAntifertilityActionYUANYu-ying;(袁玉英)ZHANGYan-lin;(张燕林)SHIQi-xian(石其贤)(Zhe... 相似文献
45.
Summary Paravertebral (superior cervical and stellate), prevertebral (coeliac-superior mesenteric, inferior mesenteric) and pelvic (hypogastric) sympathetic ganglia of the rat were investigated by enzyme histochemistry to ascertain the distribution of nicotinamide adenine dinucleotide phosphate diaphorase (NADPH-diaphorase) activity. In the paravertebral ganglia the majority of the sympathetic neuronal perikarya contained lightly and homogeneously distributed formazan reaction product but there was a range of staining intensities amongst the neuron population. In contrast, in the prevertebral ganglia, intense NADPH-diaphorase staining was present in certain neurons. Firstly, a population of neurons of the coeliac-superior mesenteric ganglion complex were surrounded by densely NADPH-diaphorase-positive baskets of fibres and other stained fibres were seen in interstitial nerve bundles and in nerve trunks connected to the ganglion complex. Secondly, in both the inferior mesenteric ganglion and hypogastric ganglion there were many very intensely NADPH-diaphorase positive neurons. Stained dendritic and axonal processes emerged from these cell bodies. In both ganglia this population of neurons was smaller in size than the lightly stained ganglionic neurons and commonly had only one long (presumably axonal) process. The similarity of these highly NADPH-diaphorase-positive neurons with previously described postganglionic parasympathetic neurons in the hypogastric ganglion is discussed. 相似文献
46.
J. -P. Timmermans M. Barbiers D. W. Scheuermann W. Stach D. Adriaensen M. H. A. De Groodt-Lasseel 《Cell and tissue research》1993,272(1):49-58
The small intestine of the pig has been investigated for its topographical distribution of enteric neurons projecting to the cranial mesenteric ganglion, by using Fast Blue or Fluorogold as a retrogradely transported neuronal tracer. Contrary to the situation in small laboratory animals such as rat and guinea-pig, the intestinofugally projecting neurons in the porcine small intestine were not restricted to the myenteric plexus, but were observed in greater numbers in ganglia of the outer submucous plexus. The inner submucous plexus was devoid of labelled neurons. Retrogradely labelled neurons were mostly found, either singly or in small aggregates, in ganglia located within a narrow border on either side of the mesenteric attachment. For both nerve networks, their number increased from duodenum to ileum. All the retrogradely labelled neurons exhibited a multidendritic uniaxonal appearance. Some of them displayed type-III morphology and stained for serotonin. This study indicates that, in the pig, not only the myenteric plexus but also one submucous nerve network is involved in the afferent component of intestino-sympathico-intestinal reflex pathways. The finding that some of the morphologically defined type-III neurons participate in these reflexes is in accord with the earlier proposal that type-III neurons are supposed to fulfill an interneuronal role, whether intra- or extramurally. 相似文献
47.
During regeneration of the neural ganglion in Ciona intestinalis, the pattern of reappearance of some peptidergic cells is similar to the ontogenetic patterns exhibited by these cell types during normal post-metamorphic development. Using a specific antiserum to gamma-aminobutyric acid (GABA), we describe here the appearance of GABA-ergic cells in Ciona during both post-metamorphic development and regeneration of the neural ganglion following total ablation. Post-metamorphic animals were divided into the categories: 1, 3–5, 6–10, 11–15 and 23–27 mm in body length. Regeneration was monitored at 12, 15, 18, 21, 28 and 56 days post ablation. The first appearance of GABA-like immunoreactive cells during normal development were at the 3 to 5-mm stage where they were seen as discrete cells, without processes, evenly distributed in the cortical region throughout the ganglion. Fibres were first seen at the 6 to 10-mm stage. As development proceeded, GABA-like immunoreactive cells became more concentrated near the nerve root exits and along the dorsal rind of the ganglion. In regenerating ganglia, GABA was first detected at 18–21 days post ablation, in cells that lacked any obvious processes and that were distributed in all regions of the ganglion. At 28 days post ablation, processes could be detected in the neuropile, and after 56 days GABA cells were found predominantly in the same regions as in the normally developing adult ganglion. Although the overall pattern reflects that in a normal adult, a few differences were detectable. For example, rather more GABAergic cells were concentrated ventrally in the ganglion close to the neural gland. 相似文献
48.
K. Tazaki C. Chiba 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1993,173(1):85-101
Cellular properties and modulation of the identified neurons of the posterior cardiac plate-pyloric system in the stomatogastric ganglion of a stomatopod, Squilla oratoria, were studied electrophysiologically. Each class of neurons involved in the cyclic bursting activity was able to trigger an endogenous, slow depolarizing potential (termed a driver potential) which sustained bursting. Endogenous oscillatory properties were demonstrated by the phase reset behavior in response to brief stimuli during ongoing rhythm. The driver potential was produced by membrane voltage-dependent activation and terminated by an active repolarization. Striking enhancement of bursting properties of all the cell types was induced by synaptic activation via extrinsic nerves, seen as increases in amplitude or duration of driver potentials, spiking rate during a burst, and bursting rate. The motor pattern produced under the influence of extrinsic modulatory inputs continued for a long time, relative to that in the absence of activation of modulatory inputs. Voltage-dependent conductance mechanisms underlying postinhibitory rebound and driver potential responses were modified by inputs. It is concluded that endogenous cellular properties, as well as synaptic circuitry and extrinsic inputs, contribute to generation of the rhythmic motor pattern, and that a motor system and its component neurons have been highly conserved during evolution between stomatopods and decapods.Abbreviations AB
anterior burster neuron
- CoG
commissural ganglion
- CPG
central pattern generator
- lvn
lateral ventricular nerve
- OG
oesophageal ganglion
- pcp
posterior cardiac plate
- PCP
pcp constrictor neuron
- PD
pyloric dilator neuron
- PY
pyloric constrictor neuron
- son
superior oesophageal nerve
- STG
stomatogastric ganglion
- stn
stomatogastric nerve 相似文献
49.
Tadashi Kawakami Naoshi Hikawa Tatsumi Kusakabe Masato Kano Yoko Bandou Hideki Gotoh Toshifumi Takenaka 《Developmental neurobiology》1993,24(5):545-551
The inhibitory effect of capsaicin on axoplasmic transport in cultured dorsal root ganglion cells was analyzed by video-enhanced contrast microscopy. Capsaicin inhibited particle transports in a dose-dependent manner, irrespective of the diameter of axons. The effect of capsaicin was reversible at low concentrations. Capsaicin affected both the anterograde and retrograde transport. Large organelles were more sensitive to capsaicin than small ones in the retrograde transport. An experiment using calcium-sensitive dye, Fura 2, indicated that capsaicin raised the intraneuronal free calcium concentration preceding the inhibition of the transport. Electron microscopy revealed that microtubules and neurofilaments are disorganized and disoriented by capsaicin. We reached a conclusion that capsaicin inhibits fast axoplasmic transport of both anterograde and retrograde directions in all types of somatosensory neurons in culture by disorganizing intraaxonal cytoskeletal structures, through the elevated intracellular Ca2+ concentration. © 1993 John Wiley & Sons, Inc. 相似文献
50.
摘要 目的:探讨血清肿瘤标志物与宫颈癌病理特征的关系及对术后复发的预测研究。方法:选择2015年1月至2017年12月来我院诊治的宫颈癌患者82例作为观察组,选择同期来我院体检的健康女性者50例,两组均使用电化学发光免疫分析法检测血清中的CA125、CA153、CA199、CEA水平,观察组患者随访时间截至2022年12月。对比两组血清CA125、CA153、CA199、CEA水平,分析观察组患者血清CA125、CA153、CA199、CEA水平与临床病理特征的关系,分析观察组患者术后随访复发情况,宫颈癌根治术后患者复发的单因素与多因素Cox回归结果,血清CA125、CA153、CA199、CEA水平对宫颈癌根治术后复发的预测价值。结果:观察组的血清CA125、CA153、CA199、CEA水平明显较对照组高(P<0.05)。宫颈癌患者不同FIGO分期、间质浸润深度及是否存在淋巴结转移间血清CA125、CA153、CA199、CEA水平对比有统计学意义(P<0.05)。82例患者随访时间为13~60个月,中位生存时间为39个月,截止2022年12月末次随访,82例患者术后复发18例(21.95%)。单因素及多因素Cox回归分析表明,FIGO分期在ⅡA期、间质浸润深度≥1/2、有淋巴结转移、CA125≥307.41 U/mL、CA153≥185.89 U/mL、CA199≥153.23 U/mL、CEA≥30.15 ng/mL是影响宫颈癌术后复发的独立危险因素。ROC曲线显示,CA125+CA153+CA199+CEA预测宫颈癌术后复发的AUC明显较CA125、CA153、CA199、CEA单独指标预测价值高(P<0.05)。结论:宫颈癌患者血清CA125、CA153、CA199、CEA高表达,其与间质浸润深度、FIGO 分期、淋巴结转移、术后复发有关,四者联合可作为宫颈癌术后复发的预测指标。 相似文献