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1.
Abstract: Experiments were designed to test the hypothesis that ganglionic butyrylcholinesterase (BuChE) is derived from acetylcholinesterase (AChE). At 5 to 8 days following preganglionic denervation of the right superior cervical ganglion (SCG), cats were given sarin, 2.0 μmol/kg, i.v. At intervals of 1 h and 1, 2, 3, 6, 11, and 22 days later, they were killed, and the AChE and BuChE contents of both SCG and both stellate ganglia (StG) were assayed. The regeneration of AChE in the normal ganglia occurred in two phases: an initial rapid phase, to 25-40% of control activity in 1 day, and a slow phase, to approximately 70% of control activity in 22 days. BuChE reached approximately 85% of control activity in normal SCG and StG at 22 days. In the denervated SCG, AChE activity reached a maximum of approximately 17% of normal at 1 day, the value prior to the administration of sarin, and did not increase appreciably above this subsequently. BuChE activity in the denervated SCG reached approximately 50% of normal ganglia at 22 days. At each interval, its activity approached 55% of that of the contralateral normal SCG, the value found in the denervated SCG prior to the administration of sarin. Hence, the regeneration of BuChE appears to be independent of the presence of AChE in the neuropil. The origin of ganglionic BuChE remains obscure.  相似文献   

2.
Acetylcholinesterase (AChE) in the clonal NG108-15 cell line has been previously characterized. This cell line represents an in vitro system to study AChE regulation and effects of chemical compounds that may alter AChE activity. Recently, glycyl-L-glutamine (GLG) was demonstrated to function as a neurotrophic factor for maintenance of AChE content in cat denervated superior cervical ganglion cells. In the present study, regeneration of AChE activity in cultures of undifferentiated NG108-15 cells after soman inhibition was investigated in the presence and absence of GLG. Cells were treated with soman (5.5 × 10–6 M) for 15 min and then washed to remove excess soman. Culture medium containing either GLG (10–6, 10–5, or 10–4M) or glycyl-L-glutamic acid (10–6 M) was added to cultures after soman treatment and remained in the medium until cell harvest. Cells were physically detached at various times after soman treatment and specific AChE activity was determined. After soman, AChE activity dramatically decreased to less than 1% of untreated cellular activity at 1 hr. AChE activity gradully increased after 5 hr, while untreated cell AChE activity was regained 20 hr after soman. The t1/2 for AChE regeneration was approximately 10 hr. GLG did not increase the rate of AChE regeneration after soman inhibition. These results indicate that GLG is not a directly acting neurotrophic factor for AChE synthesis in NG108-15 cells after chemical AChE inactivation.Abbreviations AChE acetylcholinesterase - NG108-15 cell neuroblastoma-glioma 108-15 cell - DMEM Dulbecco's modified Eagles minimal essential medium - FBS fetal bovine serum - GLGA glycyl-L-glutamic acid - L-GA L-glutamic acid - GLG glycyl-L-glutamine - GD soman The opinions or assertions contained herein are the private views of the authors and are not to be construed as reflecting the view of the Department of the Army or the Department of the Army or the Department of Defense.  相似文献   

3.
The regeneration of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) was followed in the superior cervical (SCG), stellate (StG), and ciliary (CG) ganglia and inferior oblique (IO) muscle of cats for the 3-day period following their inactivation by isopropylmethylphosphonofluoridate (sarin; 2.0 μmol/kg intravenously), with and without preservation of over half the butyrylcholinesterase activity by the prior intravenous infusion of 10-(α-diethylaminopropionyl) phenothiazine HCl (Astra 1397; 100 or 200 μmol/kg). Rates of regeneration of AChE in the three ganglia exhibited the same sequence as their relative proportions of AChE-containing cholinergic ganglion cells (SCG < StG < CG); no such difference was found in the rates of butyrylcholinesterase regeneration. The mean AChE levels in all three ganglia were higher at 48 h in the cats that had received Astra 1397 (100 μmol/kg) prior to sarin. This finding is interpreted as evidence that BuChE may function as a precursor in the synthesis of AChE.  相似文献   

4.
The transsynaptic regulation of acetylcholinesterase (AChE) was studied by recording the changes in enzymatic activity following denervation in two types of autonomic ganglia in the frog, Rana pipiens. Opposite effects on AChE were found in the parasympathetic cardiac ganglion and in the sympathetic lumbar ganglion; denervation produced a significant increase in AChE activity in cardiac ganglia but a significant decrease in lumbar ganglia. The relative effects of denervation on intracellular and total AChE were examined by selectively inhibiting extracellular AChE with echothiophate, a poorly lipid-soluble cholinesterase inhibitor. Denervation resulted in a significant increase in intracellular AChE in cholinergic cardiac ganglia but had no effect on intracellular AChE activity in adrenergic lumbar ganglia. Histochemical studies revealed little change in extracellular AChE staining upon denervation in the cardiac ganglion, whereas in the lumbar ganglia there was a loss of AChE-specific reaction product. These results raise the possibility that the transsynaptic control of AChE activity by innervation in the frog is influenced by the transmitter synthetic properties of the postsynaptic ganglion cells.  相似文献   

5.
Summary

A hormone secreted by the cerebral ganglion of Nereis promotes growth and exerts an inhibitory influence in sexual maturation. During the final stages of life, there is a sharp decline in the rate of endocrine activity. The ganglion of an immature specimen can be deactivated by exposure to the milieu of the maturing animal, although a prolonged period of time (several months at least) is required to accomplish this effect. The brain of a specimen approaching maturity is more readily deactivated and this process is not dependent on maintenance of the normal nervous connections. The deactivation process can be blocked, even after its initiation, by transplantation of the ganglion into an immature host. The process by which the population of oocytes becomes homogeneous during the penultimate stage of maturation is not dependent on the concurrent decline in endocrine activity. Posterior regeneration is not directly inhibited by the presence in the body of maturing oocytes.  相似文献   

6.
In the present paper we have comparatively analyzed acetylcholinesterase (AChE) and cholinacetyltransferase (ChAT) activity in chick and pigeon ciliary ganglion. AChE specific activity in the pigeon ciliary ganglion is remarkably higher than the one occurring in the chick; conversely the ChAT specific activity is similar in the chick as well as in the pigeon. Higher AChE activity found in the pigeon ciliary ganglion can be partially attributed to a selective accumulation of the enzyme in already described membrane-limited formations typical of the choroid neurons. After post-ganglionic axotomy such formations undergo a progressive disappearance which parallels the decrease of AChE activity. The present data suggest the hypothesis that the structures under investigation as well as ganglionic AChE are possibly controlled through a retrograde mechanism by their target organ.  相似文献   

7.
Abstract— The effects of selective inactivation of propionylcholinesterase (PrChE) by tetramonoisopropylpyrophosphortetramide (iso-OMPA) on the steady state and regenerating levels of acetylcholinesterase (AChE) were investigated on the superior cervical ganglion (SCG) of the rat. Over the dosage range of 1.5-40.0 μmol iso-OMPA/kg intraperitoneally, which produced nearly total inactivation of ganglionic PrChE and 0-35% inactivation of AChE, there was no subsequent increase in AChE activity above the control level. Single or repeated injections of iso-OMPA at total doses of 5.0-40.0 μmol/kg intraperitoneally caused no reduction in the rate of regeneration of ganglionic AChE during the 24 h following its inactivation by sarin, 2.0 μmol/kg intravenously. Both sets of findings differ from those obtained previously in a similar study of ganglionic AChE and butyrylcholinesterase (BuChE) in the cat. Possible reasons for this distinct species difference are discussed.  相似文献   

8.
Cercal ablation caused a significant loss in acetylcholinesterase (AChE) activity of the cercal nerves and terminal ganglion within 12 hr while a similar reduction in enzyme activity of connectives was noticed at least one day after cercectomy. The decrease in AChE activity of the nervous tissues showed a recovery toward control levels from 20 days of unilateral cercectomy whereas the bilateral cercectomy produced a continuous and irreversible decline in enzyme activity. These localized changes in AChE activity of the abdominal nervous system of the cockroach were attributed to be regulated by the cercal sensory innervation.  相似文献   

9.
用液氮骤冻造成大白鼠交感节前神经变性后,通过神经末梢乙酰胆碱含量、胆碱酯酶活性测定以及电刺激交感干时外周反应等研究其再生规律。结果表明冻伤后3周内再生过程进展迅速,神经结构与功能均有相当程度的恢复;3周后再生过程转慢,直至一年时各指标仍远未达到正常。这证明交感节前神经的再生过程不同于中枢及其它外周神经而独具特征。  相似文献   

10.
Summary Acetylcholinesterase (AChE, EC 3.1.1.7) and choline acetyltransferase (CAT, EC 2.3.1.6) activities where studied in the early development of the chick embryo. A sharp increase in AChE activity occurred in the gastrulating embryo. The highest AChE activity was associated with hypoblast cells. By sucrose density gradient centrifugation three molecular forms of AChE with sedimentation coefficients 4.7 S, 6.8 S and 10.9 S were determined. During the gastrulation there was no remarkable change in the activity of CAT. A two-fold decrease in the CAT activity occurred at the end of gastrulation.  相似文献   

11.
Abstract Recovery of AChE activity in the motor end plate region and end plate free region of the rat diaphragm was studied after irreversible inhibition by soman. Recovery was slow during the first 2 days and only 4 S and 10 S molecular forms of AChE were present in the end plate region. However, cytochemical evidence indicates that synaptic AChE has already started to accumulate and that the synthesis of AChE in muscle and Schwann cell might even be enhanced. Tubular structures, observed underneath the motor end plate, may serve to transport the enzyme from its sites of synthesis in the sarcoplasmic reticulum. Asymmetric molecular forms of AChE in the end plate region appeared later during recovery and, one week after poisoning, their activity was only about 50% of normal value. The limited ability of newly synthesized AChE to attach to the subcellular structures and, therefore, to be retained in the muscle, may explain the phase of slow recovery. In accordance with this view, AChE activity in brain recovered in a similar way as in muscle, whereas soluble plasma cholinesterases recovered faster, apparently without a slow initial phase.  相似文献   

12.
Abstract: Four main molecular forms of acetylcholinesterase (AChE) characterized by their sedimentation coefficients (5S, 7.5S, 11.5S, and 20S), are found in chick ciliary ganglion. After transection of the preganglionic nerve (denervation), total AChE activity in the ganglion dropped by 35% in 2 days. By then, 11.5s and 20s forms had diminished by 60 and 75% respectively, where as 7.5s remained practically unchanged. Since presynaptic structures disappeared 2 days after denervation, we inferred that at most 35% of total ganglion AChE was presynaptic: 11.5s and 20s might be mainly presynaptic and 7.5S, postsynaptic. At later time intervals. total AChE continued to decline up to day 5, possibly as a result of orthograde transynaptic regulation of the enzyme activity. After transection of postganglionic nerves (axotomy), total ganglion activity showed little change; 11.5s and 20s decreased by 40 and 6076, respectively, in 5 days, but these drops were compensated for by an early increase in 7 5S, which started the day after axotomy. After simultaneous transection of both pre- and postganglionic nerves (double section), total ganglion AChE dropped rapidly by 35% in 1 day and remained at that level up to 21 days. The 11.5S diminished rapidly by 60% in 1 day. The early increase of the 7.5s form induced by axotomy alone did not occur. Since the effect resulting from double section was not the equivalent of the cumulative effects observed after denervation and axotomy, respectively, the level of AChE forms in the ganglion may be regulated by reciprocal interaction of pre- and postsynaptic elements. After denervation and double section but not after axotomy alone, the contralateral non-operated ganglion exhibited a fall in the 20s form. This suggests that a transynaptic effect is exerted on AChE by the contralateral preganglionic neuron. Taken together, these results indicate that the various AChE molecular forms in chick ciliary ganglion are preferentially but not exclusively distributed as follows: the pre- and postganglionic axons contain mainly the 11.5S form, whereas nerve endings and synaptic structures are enriched in 20S, and ganglion cell bodies, in 7.5s.  相似文献   

13.
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   

14.
为了探讨心内神经节中去甲肾上腺素(NA)、乙酰胆碱(ACh)和NPY的相互作用,本实验应用6-OH-DA选择性切除大鼠心脏交感神经纤维,然后应用荧光和酶组织化学法、免疫组织化学结合图像分析法观察了大鼠心内神经节NA、AChE活性和NPY的变化。结果显示:实验组大鼠心内神经节中儿茶酚胺荧光反应阳性和NPY免疫反应(NPY-IR)阳性的神经纤维明显减少,AChE阳性神经纤维明显增多,AChE反应性神经元积分光密度增加,而儿茶酚胺荧光反应和NPY-IR阳性神经元变化不明显。结果提示:1.交感神经化学切除后大鼠心内神经节中NA、AChE活性和NPY出现不同的变化,体现了心脏交感神经和副交感神经的相互抑制作用;2.心内神经节可能含有两种性质的NPY,即交感性和非交感性NPY。  相似文献   

15.
The activity of acetylcholinesterase (AChE) and the density of muscarinic cholinergic binding receptors (mCBR) were measured in brains from normal Japanese quail (Coturnix coturnix japonica) and from quail after lethal intoxication with diazinon. These were measured in brains from whole heads held at 25 C for 0 to 8 days after death. The maximum relative loss of activity due to post mortem decomposition alone during 8 days was 13% and 10% for AChE and mCBR, respectively. During post mortem decomposition, the ratio of AChE: mCBR activities remained constant at approximately 1.3:1 in normal brains while it was always less than or equal to 0.5:1 after intoxication with diazinon. Normal AChE activity could be estimated from mCBR density. Parallel measurement of AChE and mCBR may assist in the post mortem diagnosis of death due to acute poisoning with anti-cholinesterase pesticides when control specimens are not available.  相似文献   

16.
Enchytraeus japonensis is a small terrestrial oligochaete which primarily reproduces asexually by fragmentation and regeneration. In order to introduce a molecular approach to the study of regeneration we developed a whole-mount immunostaining procedure for the worm. Using an antibody directed against acetylated tubulin in conjunction with confocal laser-scanning microscopy, we succeeded in clarifying the three- dimensional structure of the entire nervous system in the full-grown worm and its dynamics during the fragmentation and regeneration process. In addition, we examined the expression of neurotransmitters and neuropeptides in the worm using a fluorescently-labeled antagonist and various antibodies. In particular, we found two circumferential structures in the body wall muscle of each segment that react strongly with α-bungarotoxin, an antagonist of nicotinic acetylcholine receptors, and detected nerve fibers just underneath these structures. During the fragmentation process, the circular body wall muscles contract near one of these circumferential structures in the middle of the segment, which causes constriction and results in fission of the body. This α-bungarotoxin-positive structure was designated the neuromuscular junction of the circular muscle. During the regeneration process nerve fibers grow from the remaining ventral nerve cord and gradually form networks in both the anterior and posterior regeneration buds. The growing fibers extend to the prostomium (a sensory organ) at the anterior end prior to connecting to the presumptive brain rudiment. A neural network appears around the pygidium, and this is followed by growth of the body at the posterior end. The nervous system appears to play an important role in both anterior and posterior regeneration. Received: 9 June 1999 / Accepted: 30 December 1999  相似文献   

17.
Abstract— In sucrose gradient centrifugation, acetylcholinesterase (AChE, EC 3.1.1.7.) from the rat superior cervical ganglion (SCG) has been found to contain four molecular forms, characterized by their sedimentation coefficients (4 S, 6.5 S, 10 S and 16 S). Homogenization of the ganglia in various media showed that the 4 S enzyme was readily solubilized in water whereas solubilization of the 6.5 S and 10 S forms was quantitative only in media containing Triton X-100. In order to solubilize the 16 S form, high concentrations of salt (NaCl 1 M) and detergent had to be present. AChE analysed by non-denaturing polyacrylamide gel electrophoresis separated into five bands. Although both distribution patterns were stable, i.e. each form or band preserved its characteristic sedimentation or electrophoretic migration when reanalysed, there was no 1:1 correlation between the forms isolated by sedimentation and the bands obtained by electrophoresis: one band might contain more than one form of enzyme, and conversely one form gave rise to several bands. It was therefore impossible to derive molecular weights from electrophoretic migration in non-denaturing gels. However, it could be shown that the results obtained by both methods of analysis were consistent. Acetylcholinesterase from other nervous structures was analysed: in pre- and postganglionic nerves, the main forms were 10 S and 6.5 S, with a small proportion of 4 S; the 16 S form was not detected. In other sympathetic ganglia, the distribution of forms was identical to that of the superior cervical ganglion. In rachidian ganglia, no 16 S form could be found. Following the section of the preganglionic nerve, the acetylcholinesterase activity of the superior cervical ganglion decreased by 50% in 3 days, and then rose again to about 80% of its original value after 2 weeks. These effects mainly reflected variations in the major 4 S and 10 S forms. The 16 S form, in contrast to its disappearance from denervated muscles, increased transiently during the first 2 weeks after denervation, reaching about twice its original activity. A concomitant cytochemical study of normal and denervated ganglia showed that after preganglionic denervation, AChE localized in the sympathetic neurones decreased markedly and remained low even during the recovery phase. During this period a cholinesterasic activity appeared in the perineuronal glia. Controls established that the enzyme synthetized in the glia is AChE.  相似文献   

18.
Immunohistochemistry has been used to demonstrate tyrosine hydroxylase (TH), dopamine--hydroxylase (DBH), phenylethanolamine N-methyltransferase (PNMT), neuropeptide Y (NPY) and vasoactive intestinal polypeptide (VIP) immunoreactivities, and acetylcholinesterase (AChE) activity was demonstrated in rat adrenal glands. The TH, DBH, NPY and VIP immunoreactivities and AChE activity were observed in both the large ganglion cells and the small chromaffin cells whereas PNMT immunoreactivity was found only in chromaffin cells, and not in ganglion cells. Most intraadrenal ganglion cells showed NPY immunoreactivity and a few were VIP immunoreactive. Numerous NPY-immunoreactive ganglion cells were also immunoreactive for TH and DBH; these cells were localized as single cells or groups of several cells in the adrenal cortex and medulla. Use of serial sections, or double and triple staining techniques, showed that all TH- and DBH-immunoreactive ganglion cells also showed NPY immunoreactivity, whereas some NPY-immunoreactive ganglion cells were TH and DBH immunonegative. NPY-immunoreactive ganglion cells showed no VIP immunoreactivity. AChE activity was seen in VIP-immunopositive and VIP-immunonegative ganglion cells. These results suggest that ganglion cells containing noradrenaline and NPY, or NPY only, or VIP and acetylcholine occur in the rat adrenal gland; they may project within the adrenal gland or to other target organs. TH, DBH, NPY, and VIP were colocalized in numerous immunoreactive nerve fibres, which were distributed in the superficial adrenal cortex, while TH-, DBH- and NPY-immunoreactive ganglion cells and nerve fibres were different from VIP-immunoreactive ganglion cells and nerve fibres in the medulla. This suggests that the immunoreactive nerve fibres in the superficial cortex may be mainly extrinsic in origin and may be different from those in the medulla.  相似文献   

19.
When rat soleus muscles fibers regenerated after notexin-induced damage, AChRs were present at high density on the surface of the new muscle fibers at the sites of the original NMJs, even if the intact motor axons were not present during regeneration. Some AChR molecules which were labelled with R-BgTx before notexin-induced damage persisted for some days at junctional sites after new muscle fibres had regenerated. During muscle fiber degeneration, components of the muscle fiber plasma membrane appeared to remain longer in the junctional region than elsewhere. When muscles on which new "ectopic" NMJs had been forming for at least 2 weeks were damaged, AChR clusters together with sites of high AChE activity were present 2 weeks later on the regenerated muscles in the region of new NMJ formation, even if the "foreign" nerve was not intact during the period of regeneration. If ectopic NMJs had been forming for only 4 days at the time of muscle and nerve damage, neither AChR clusters nor AChE activity were detected on the regenerated muscle fibers.  相似文献   

20.
In the nine day old embryo, acetylcholinesterase (AChE) is found in the reticulum, i.e. the nuclear envelope, endoplasmic reticulum, and Golgi complex, of a few cells in the neural crest. When the neurite first enters the neural tube, reticulum-bound enzyme is present also in the varicosity of the growth cone of the bipolar neuroblast. At later stages, AChE in the neuroblast has a dual distribution; in addition to the reticulum, activity also appears at the axolemmal surface. The axolemmal activity is found initially on the distal portions of axons in the posterior fasciculus and then progressively appears along the nerve roots in a distal to proximal direction. Very little reticulum-bound enzyme is present within the axon proper. After the 13th day the levels of AChE activity in the posterior fasciculus greatly exceed those in the dorsal root or in the ganglion. Enzymatic activity in the dorsal root equals or exceeds that in the posterior fasciculus by day 16, and both areas are considerably more active than the ganglion.  相似文献   

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