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1.
1. Apart from octopamine, the same indolamines and catecholamines were detected in the whole nervous system of the cockroach Blaberus craniifer Burm., at the same time.2. However, levels were found to depend on sex, age, and the anatomic region within the nervous system.3. Although not established, it is thought that these substances act synchronously from the ganglia.4. The differences in levels between males and females and between anatomical regions during imaginal life suggest, in this species of cockroach, the physiological importance of the metameric organization in metabolic pathways or functional aspects of biogenic amines.  相似文献   

2.
1. Indolamines were assayed by HPLC-ECD in nervous tissue of fed and crowded young males Blaberus craniifer Burm. 2. In males, as in females housed in the same conditions, levels are depending on both age and region (= ganglia) of the central nervous system. 3. Registered sex differences are discussed in terms of anatomical, physiological and behavioral sexual dimorphism.  相似文献   

3.
P Sourander 《Biorheology》1991,28(6):491-525
The application of principles of biorheology, hemorheology and perihemorheology on problems of the nervous system in health and disease was suggested by Alfred L. Copley (1982, 1987). Late in 1988 Copley and Sourander considered neurobiorheology to be an appropriate term for a new branch of biorheology bridging the gap between biorheology and neurobiology. Neurobiorheology can be defined as a research field concerned with deformation behaviour of matter including flow and transportation in context with the structure and function of the nervous system at macroscopic, cellular, subcellular and molecular levels. It may be considered a basic life science with important clinical applications. Its "raison d'être" should be to apply various ways of thinking, calculations and techniques used in biorheology to treat and if possible to solve neurobiological problems. Many regionally different chemical, structural and functional properties characterize the developing and adult nervous system and those parts of the circulatory system ("vessel-blood organ") which penetrate the nervous system at all levels. Considering the close metabolic and functional relations between neurons and surrounding non-neuronal ectodermal cells, neuroglial and Schwann cells deriving from common precursor cells in the wall of the neural tube and neural crest respectively, the term neuroectodermal organ appears suitable. The almost parallel ontogenetic evolution of vessel-blood organ and neuroectodermal organ and their interaction during the entire individual life cycle constitutes a challenging stimulus for integrated research. The main purpose of this review is to give some examples of importance concerning still insufficiently elucidated neurobiological problems suitable for biorheological approaches. Particular attention will be paid to the microenvironment at central and peripheral levels of the neuroectodermal organ.  相似文献   

4.
The human brain contains 100 billion neurons and probably one thousand times more synapses. Such a system can be analyzed at different complexity levels, from cognitive functions to molecular structure of ion channels. However, it remains extremely difficult to establish links between these different levels. An alternative strategy relies on the use of much simpler animals that can be easily manipulated. In 1974, S. Brenner introduced the nematode Caenorhabditis elegans as a model system. This worm has a simple nervous system that only contains 302 neurons and about 7,000 synapses. Forward genetic screens are powerful tools to identify genes required for specific neuron functions and behaviors. Moreover, studies of mutant phenotypes can identify the function of a protein in the nervous system. The data that have been obtained in C. elegans demonstrate a fascinating conservation of the molecular and cellular biology of the neuron between worms and mammals through more than 550 million years of evolution.  相似文献   

5.
目的:探讨中枢神经系统感染患儿血清和脑脊液C反应蛋白(CRP)、降钙素原(PCT)、肿瘤坏死因子-α(TNF-α)及基质金属蛋白酶-9(MMP-9)水平及其临床意义。方法:选择2017年1月~2018年6月期间南京市第二医院收治的中枢神经系统感染患儿93例作为研究对象,其中化脓性脑膜炎62例记为化脓性脑膜炎组,病毒性脑炎31例记为病毒性脑炎组,另选取同期于我院治疗的非中枢神经系统感染患儿40例作为对照组,比较各组血清、脑脊液CRP、PCT、TNF-α、MMP-9水平及阳性率,并计算血清和脑脊液CRP、PCT、TNF-α、MMP-9诊断中枢神经系统感染的灵敏度、特异度及准确度。结果:化脓性脑膜炎组患儿血清、脑脊液CRP、PCT、TNF-α及MMP-9水平及阳性率高于病毒性脑炎组和对照组,病毒性脑炎组患儿血清、脑脊液CRP、TNF-α及MMP-9水平及阳性率高于对照组(P<0.05),病毒性脑炎组与对照组血清、脑脊液PCT水平及阳性率比较无统计学差异(P>0.05)。血清或脑脊液CRP+PCT+TNF-α+MMP-9联合检验对中枢神经系统感染具有一定的诊断价值。结论:中枢神经系统感染患儿血清、脑脊液CRP、TNF-α、PCT及MMP-9水平明显升高,其中化脓性脑膜炎患儿血清、脑脊液PCT水平高于病毒性脑炎患儿,血清或脑脊液CRP、PCT、TNF-α及MMP-9联合检验对儿童中枢神经系统感染的鉴别诊断具有较高的价值。  相似文献   

6.
The levels of choline intermediate endogenous pools in structures of the visual system (retina, optic nerve, lateral geniculate body, superior colliculus) and in sciatic nerve of adult (4-month-old) and young (30-day-old) rats were measured. The amounts were also obtained from retina, optic nerve, optic tectum and cranio-spinal nerves of a primitive elasmobranch, the smooth dogfish Mustelus canis, and from related nervous structures (retina, optic lobe, fin nerve, stellar nerve and stellate ganglia) of a marine invertebrate, the squid Loligo pealei. In all regions of rat nervous system, the pool size of CDP-choline was much smaller than that of free choline, whereas GroPCho was present in a relatively higher content. The pool sizes of choline intermediates in 30- and 120-day-old rats were nearly the same. In nervous system regions of the dogfish and squid, the values followed the same general trend as observed for rat. Squid nervous tissues had the lowest choline and GroPCho contents. The rat retina showed the lowest glycerophosphorylcholine phosphodiesterase activity. The chemical studies described here confirm the basic similarity in the pattern of choline intermediate pool sizes among animal species widely different in phylogenetic position. The data highly reinforce the idea that the precursor role of choline and catabolic pathways for the maintenance of the PtdCho membraneous pool seem highly conserved during evolution.  相似文献   

7.
R Kwok  D R N?ssel  A B Lange  I Orchard 《Peptides》1999,20(6):687-694
The presence of locustatachykinin (LomTK)-like immunoreactivity is demonstrated in the central nervous system (CNS) of Locusta migratoria with the use of a polyclonal antiserum raised against LomTK1. By developing a radioimmunoassay with the same antiserum, we have demonstrated picomolar amounts of LomTK-like material in the tissues of the central nervous system. In contrast, only femptomolar amounts of LomTK-like material are associated with the oviduct tissue. The relative amounts of the different LomTK isoforms in the brain and the abdominal ganglionic chain were examined by separating the native peptides on high-performance liquid chromatography and comparing their retention times to synthetic LomTK standards. The amounts of the different isoforms of LomTK differed between and within the two regions of the central nervous system. However, the ratios of the different isoform amounts were similar between the two regions. The myostimulatory activities of LomTKs 1 to 4 were characterized by using the locust oviduct bioassay. LomTKs 1, 2, and 3 appeared to be more efficacious than LomTK4.  相似文献   

8.
The buccal ganglia of Helix pomatia are used as model nervous structures in neurophysiological and in epileptological studies. Many basic problems concerning membrane physics, functioning of the single neurons and of neuronal networks can be studied easily using these ganglia. The model character mainly comes from the relative simplicity of this nervous system and that it contains large visually identifiable neurons. As in other invertebrate nervous systems, the large neurons have proved to be individuals showing the same functional and structural properties from one animal to the next.  相似文献   

9.
Pyroglutamyl peptidase II (PPII) is a narrow specificity ectoenzyme that degrades thyrotropin-releasing hormone (TRH). We detected the enzyme in the brain of various mammals, with highest specific activity in rabbit brain. In this species, activity was heterogeneously distributed in the central nervous system. There was a 28-fold difference between regions of highest and lowest PPII activity. Enzyme activity was highest in the olfactory bulb and posterior cortex. In the spinal cord, activity was low but unevenly distributed, with highest values detected in the thoracic (T) region. Segments T1 and T2 activities were particularly high. Other organs contained low or undetectable levels of activity. The levels of TRH-like immunoreactivity (TRH-LI) in spinal cord segments were greatest in T3-T4 and lumbar L2-L6. Low concentrations were found in T1 and T9-T12. There was a partial correlation between the distribution of PPII activity and TRH receptors but not with TRH-LI levels. These results demonstrate that PPII is predominantly a central nervous system enzyme, and they support the hypothesis that PPII is responsible for degrading TRH released into the synaptic cleft.  相似文献   

10.
The central nervous system of the mollusc Helix pomatia, like that of other molluscs, contains a very high level of dopamine. However, noradrenaline is weakly represented. These characteristics apply to the peripheral nervous system and more particularly to the heart. The study of the phenomena taking part in the synthesis and inactivation of catecholamines shows that these processes are not different in vertebrates and molluscs. Thus, in the particular case of Helix pomatia the synthesis of catecholamines is carried out by tyrosine hydroxylase, aromatic amino acid decarboxylase and dopamine-beta-hydroxylase. These enzymes are not only active in the ganglia and nerves, but also in the peripheral nervous system. The monoamines are associated with granules. The synthesized enzymes in the pericarya migrate due to the axonal flow and accumulate in the intracardiac nerve endings. In Helix pomatia, the enzymes participate actively in the local synthesis of catecholamines using the precursors tyrosine and DOPA. We have little information on the uptake of dopamine by nervous structures, but it would seem that this phenomenon seems to play an active role in the synaptic inactivation of dopamine. The glial elements also play a part in uptake and inactivation. In most species the nervous system has very little monoamine oxidase, and there is even less in the heart. The enzymic activity depends on substrates and is more active with dopamine than with 5-hydroxytryptamine. The exact localization of monoamine oxidase in the tissues is unknown. However, we believe that it plays a part in the neuronal regulation of dopamine levels and in its synaptic inactivation. The same applies for catechol O-methyltransferase.  相似文献   

11.
The effect of the neurodepressing hormone (NDH) was studied on different identified motoneurons in the abdominal ganglia of the crayfish Procambarus bouvieri (Ortmann). Although differences in sensitivity were apparent, all the neurons tested responded to NDH with a reduction in spontaneous firing rate, which lasted as long as NDH was present, and, depending on the concentration and time of action of the hormone, for even longer periods. NDH activity was determined in the various parts of the central nervous system of the crayfish, being highest in the eyestalk, gradually diminishing away from the eyestalk, with a cephalo-caudal gradient, being lowest in the abdominal ganglia. High levels of NDH activity were detected in the blood. After eyestalk ablation, NDH concentration steadily diminishes in the blood and central nervous system, until virtually disappearing after 4 days; from day 5 onwards, the activity is recovered up to its original levels. NDH synthesis takes place with a time constant of approximately 3 hr in cultured isolated segments of central nervous system, being highest in the eyestalk.  相似文献   

12.
1. Indolamines were assayed by HPLC-ECD in nervous tissue of fed and crowded young males Blaberus craniifer Burm.2. In males, as in females housed in the same conditions, levels are depending on both age and region (= ganglia) of the central nervous system.3. Registered sex differences are discussed in terms of anatomical, physiological and behavioral sexual dimorphism.  相似文献   

13.
Choline acetyltransferase in individual neurons of Aplysia californica   总被引:3,自引:1,他引:2  
The activities of choline acetyltransferase in the various ganglia of the nervous system of Aplysia californica and in some of the individually identifiable neurons in these ganglia were measured. At least four of the neurons were characterized by an apparent absence of the enzyme. The neurons containing measurable amounts of the enzyme had reproducible levels from animal to animal. Individual neurons from the same animal were generally characterized by different levels of activity whether expressed on a cell or a protein basis. However, those pairs of neurons previously classified as ‘homologous’ because of their similar appearance, location and/or electrophysiological function, also contained the same total amounts of enzyme activity.  相似文献   

14.
Chromogranin A (CgA) is an acidic protein co-released with catecholamines during exocytosis from sympathetic nerve terminals and chromaffin cells. Previous work has demonstrated that large scale perturbations in sympathetic nervous system (SNS) functioning result in corresponding changes in CgA levels in plasma. Little is known about the physiologic significance of CgA. We hypothesized that, since CgA and catecholamines are co-released from the same storage vesicles, and since CgA is not subject to reuptake or enzymatic metabolism, plasma CgA should reflect norepinephrine release from sympathetic terminals. We therefore measured venous CgA, norepinephrine levels, and norepinephrine release rate in 30 unmedicated subjects. Although the correlation of CgA with plasma norepinephrine was only modest (r = 0.37, p less than 0.05), its correlation with norepinephrine release rate was highly significant (r = 0.58, p less than 0.001). Thus, CgA may offer a novel perspective on peripheral sympathetic activity.  相似文献   

15.
A recently developed procedure for the localization of D-amino acid oxidase (D-AAO) has been used to investigate the distribution of this enzyme in rat nervous tissue. Initial studies were carried out on kidney to validate the methods. The cytochemically demonstrable enzyme in kidney is inhibited by kojic acid, a known competitive D-AAO inhibitor. Omission of the catalse inhibitor, aminotriazole, from the cytochemical medium produces a marked diminution of D-AAO reaction product in kidney peroxisomes. This would be expected if catalase and D-AAO are present in the same particles. In brain, kojic acid-inhibitable D-AAO is demonstrable in numerous bodies within astrocytes especially in the cerebellum, a brain region known from biochemistry to contain particularly high levels of the oxidase. In preparations incubated for catalase, far fewer positive bodies are seen in the cerebellum. Moreover, omission of aminotriazole has little evident effect on the D-AAO reaction. Thus, the oxidase-containing cerebellar bodies may be relatively poor in catalse. In contrast, several nervous system cell types that contain relatively numerous catalase-positive bodies, contain none with detectable D-AAO. Such heterogeneity of peroxisome enzyme content is in accord with reports from biochemical studies of brain.  相似文献   

16.
17.
A novel second myostatin gene is present in teleost fish.   总被引:9,自引:0,他引:9  
We report on the isolation and characterisation of the complete cDNA sequence encoding a novel bone morphogenetic protein-like protein (sbMSTN-b) in the teleost fish Sparus aurata. The encoded protein is 68% identical to S. aurata MSTN at the amino acid level, and homologues were also found in Umbrina cirrosa and Tetraodon nigroviridis. Phylogenetic analysis suggests that the MSTN-b gene may be present in most, perhaps all, teleost fish species. RT-PCR on different tissues/stages indicates that MSTN-b is expressed almost exclusively in the central nervous system, starting from late larval stages. Quantitative analyses indicate an increase of sbMSTN-b expression in the brain associated with metamorphosis, at the same time as completion of nervous system differentiation.  相似文献   

18.
19.
Complement-dependent demyelinating activity of whole brain homogenate (WBH)-induced experimental allergic encephalomyelitis (EAE) sera was tested on long term tissue cultures of in vitro myelinated fetal guinea pig cerebellum. Complement-fixing (CF) auto-antibodies were shown to be the responsible agents, as demonstrated in experiments where all reagents belonged to the same species: guinea pigs of outbred (Hartley) and even of inbred (S2 or S13) strains. These antibodies were of the IgG2 class as shown by Sephadex G-200 and DEAE cellulose fractionation experiments. The corresponding auto-antigen was present in the homogenate and myelin of the central nervous system (CNS) tissue. It was different from the encephalitogenic basic protein of CNS myelin (BP), as shown in experiments where the demyelinating auto-antibodies were induced, detected, and absorbed by WBH or by CNS myelin but not by BP. They were neither induced by nor cross-reacting with cerebroside and peripheral nervous system (PNS) tissue.  相似文献   

20.
Ten patients with severe neurological disease that was clinically indistinguishable from subacute combined degeneration of the spinal cord were found to have normal serum vitamin B12 levels. All were folate deficient. Specific folate treatment led to significant reversal of the neuropathy. These findings indicate the need to review orthodox concepts of the role of folic acid in maintaining the integrity of the nervous system.  相似文献   

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