ChAT Activity Research Articles

Immunohistochemical demonstration of cholinergic structures in central ganglia of the slug ( Limax maximus, Limax valentianus)

Immunohistochemical techniques were used to study the distribution of cholinergic neurons containing choline acetyltransferase of the common type (cChAT), the synthetic enzyme of acetylcholine, in the central nervous system of the slug Limax maximus and Limax valentianus. Because the antiserum applied here was raised against a recombinant protein encoded by exons 7 and 8 of the rat gene for ChAT, three methods were used in order to validate antibody specificity for the Limax counterpart enzyme. Western blot combined with ChAT activity assay following native gel electrophoresis and immunoprecipitation analysis both indicated that immunoreactive Limax brain molecules were capable of synthesizing acetylcholine. Western blot after denatured gel electrophoresis of Limax brain extracts revealed a single band of about 67 kDa. All findings obtained with these three methods clearly indicated that the antiserum effectively recognized Limax cChAT. 1400 neuronal cell bodies positive for cChAT, mainly small to medium-sized, were found in various brain regions in the buccal, cerebral, pleural, parietal, visceral and pedal ganglia. cChAT immunoreactive nerve fibers were distributed extensively in the neuropil, connectives and commissures of these central ganglia. The map of cChAT-positive cells provided here are valuable for understanding the cholinergic mechanism in the slug brain, as well as giving an important hint to clarifying the mechanisms of learning and memory in higher vertebrates including humans.

Effect of Kangshuai Yizhi Formula I (抗衰益智方 I) on learning and memory dysfunction induced by scopolamine in mice

To evaluate the improvement of Kangshuai Yizhi Formula I ( I, KYF I) on: the learning and memory dysfunction in mice, and on the mechanism of the hippocampal cholinergic system and the nervous system of monoamine which are closely related to learning and memory function. Mice: in the low-, middle-, and high-dose KYF I groups were given low-, middle-, and high-dose KYF, respectively, by gastrogavage for 35 successive days. Animals in the control group and the model group were treated with distilled water. The acute learning and memory dysfunction model was established by injection of scopolamine from day 31, and Morris water maze was used to assess the behavior performance of scopolamine-induced model mice for five days. The activities of acetylcholinesterase (AChE), choline acetyl transferase (ChaT) and the content of monoamine neurotransmitters in hippocampus were measured. The activity of monoamine oxidase (MAO) in hippocampus and serum was also detected. (1) Compared with the control group, the: mean escape latency was shortened, and the frequency across the platform and the staying time at the platform area on the 5th day were decreased in the model group by Morris water maze test. The activities of AChE and MAO were increased, and the ChaT activity and monoamine neurotransmitter content were decreased as well. (2) The escape latency for 4 days in the low-, middle-, and high-dose KYF I groups was significantly shortened than that in the model group, with the shortest latency in the high-dose KYF I group (P<0.05, P<0.01). The frequency across the platform was significantly increased and the staying time at the platform was significantly prolonged in the middle- and high-dose KYF I groups (P<0.05, P<0.01). (3) As compared with the model group, the activity of ChaT and the content of monoamine neurotransmitters in the hippocampus were significantly increased, and the activities of AchE and MAO were significantly decreased in the hippocampus in the high-dose KYF I group (P<0.01). High-dose KYF I can significantly improve the learning and memory dysfunction: induced by scopolamine in mice. Its mechanism may be related to improving the central cholinergic system and regulating the hippocampal monoamine neurotransmitters.

Neuronal re-juvenilization in the nucleus ambiguus after vagal nerve injury

Nestin is an intermediate filament expressed in immature cells in the CNS including neural stem/progenitor cells, reactive astrocytes and immature neurons in lesser amounts after injury. Nestin expression in the nucleus ambiguus following vagal nerve injury was studied using nestin-EGFP transgenic rats. We confirmed that EGFP immunoreactivity was evident at 6 h to 8 days in ipsilateral nucleus ambiguus after nerve transection. Properties of these cells were examined immunohistochemically. These EGFP-immunoreactive cells were immunoreactive for Tuj1 and Hu, and exhibited ChAT activity. However, no immunoreactivity for GFAP or CNPase was observed. In normal development, the level of KCC2 expression is known to increase with maturation of neurons. In our study, decreased KCC2 expression was observed in nestin-EGFP-positive cells within the nucleus ambiguus on the lesioned side compared with the contralateral side. These EGFP-immunoreactive cells were immunonegative for BrdU. This is the first study to demonstrate the expression of a neural stem/progenitor cell-enriched marker, Nestin, in the nucleus ambiguus after vagal nerve injury. The present findings suggest that mature motoneurons are an origin of these Nestin-positive cells, which are induced after injury. Mature neurons in the nucleus ambiguus may thus have the potential to juvenilize after vagal/recurrent laryngeal nerve injury.

Regulation of M1-receptor mRNA stability by smilagenin and its significance in improving memory of aged rats

The purpose of this work is to study the effect of smilagenin on the mRNA stability of muscarinic receptor subtype 1 (M(1); m1 mRNA) in aged rat brains and its significance in improving memory. The Y-maze avoidance task showed that oral administration of smilagenin significantly improved spatial memory performance in aged rats. Mechanistic studies showed that smilagenin was neither a ligand of the M receptors nor a cholinesterase inhibitor, while radioligand binding assays revealed that smilagenin significantly increased the M(1)-receptor density. The increase of M(1)-receptor density correlated with memory improvement. Real-time polymerase chain reaction (RT-PCR) revealed that the m1 mRNA in m1 gene-transfected CHO cells increased significantly, and the average half-life of m1 mRNA was approximately doubled by smilagenin treatment. These results suggest that smilagenin improves memory of aged rats at least partially by increasing the stability of m1 mRNA. However since the ChAT activity in the cortex of aged rats was also elevated by smilagenin, it cannot be excluded that the increase of intrinsic acetylcholine excretion also plays a role in the memory-improvement effect of smilagenin.

Anti-amnesic potentials of a novel phytochemical formulation PZA-3 in animal models relevant to Alzheimer's disease

Event Abstract Back to Event Anti-amnesic potentials of a novel phytochemical formulation PZA-3 in animal models relevant to Alzheimer's disease Joshi Hanumanthachar1* and C. Disale1 1 SET’s College of Pharmacy, India Background: Dementia is one of the age related mental problems and a characteristic symptom of Alzheimer’s disease. There has been a steady rise in the number of patients suffering from Alzheimer’s disease (AD) all over the world. It is the most common form of onset of adult dementia and attention deficit disorders. Newer drugs are continually introduced into the market with little efficacy. Hence it is worthwhile to explore the utility of traditional medicines in treatment of cognitive disorders. The Indian system of medicine, Ayurveda has been in practice since 5000 years. Objective: The main goal of the studies reported here is to investigate the cerebro-protective and memory improving potentials of phytochemicals based formulation PZA-3. Methods: β-amyloid, scopolamine, ibotenic acid, CO2 and aging induced amnesia, KCN and Carotid artery ligation-induced hypoxia were the experimental models. Basal forebrain lesion induced decrease in cerebral Ach and ChAT activity were assessed, Concentrations of Norepinerphrine, Epinephrine, Dopamine, 5-HT in cerebral cortex, cerebellum, hypothalamus, hippocampus, and corpus striatum were measured by HPLC analysis. Neuromorphology, contents of MDA, NO, activities of SOA and CAT were also measured which indicated that PZA-3 protected the animals from stress, amnesia and neurodegeneration. Results and Discussion: They inhibited KCN and Carotid artery ligation induced hypoxia, reversed amnesia and neurodegeneration and produced normalizing action on discrete regions of brain and controlled alterations in neurotransmitter levels due to neurodegeneration. They also decreased ChAT activity in the parietal cortex and inhibited decrease in Ach levels in both parietal and frontal cortex in amnesic rats. Hence PZA-3 can be of enormous use in the treatment of dementia of Alzheimer’s type and other neurodegenerative disorders. Conference: 10th International Conference on Cognitive Neuroscience, Bodrum, Türkiye, 1 Sep - 5 Sep, 2008. Presentation Type: Poster Presentation Topic: Animal Models of Cognition Citation: Hanumanthachar J and Disale C (2008). Anti-amnesic potentials of a novel phytochemical formulation PZA-3 in animal models relevant to Alzheimer's disease. Conference Abstract: 10th International Conference on Cognitive Neuroscience. doi: 10.3389/conf.neuro.09.2009.01.077 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 01 Dec 2008; Published Online: 01 Dec 2008. * Correspondence: Joshi Hanumanthachar, SET’s College of Pharmacy, Karnataka, India, amanjoshi17@yahoo.com Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Joshi Hanumanthachar C. Disale Google Joshi Hanumanthachar C. Disale Google Scholar Joshi Hanumanthachar C. Disale PubMed Joshi Hanumanthachar C. Disale Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Group Processes and Process Evaluations in a New Treatment Setting: Inpatient Group Psychotherapy Followed by Internet–Chat Aftercare Groups

Little is known about processes characterizing therapeutic Internet–chat groups, which offer a novel way of providing group therapy over distances. In this study group processes and group evaluations were examined in a treatment setting where face–to–face inpatient groups are followed by chat aftercare groups. For a sample of 121 patients who participated in both treatment modalities, group processes and group evaluations were modeled using hierarchical linear modeling. The group evaluations followed a consistent upward course from the beginning of therapy until the end of chat aftercare. For the process measures Activity and Emotional Reactivity, the initial scores at the beginning of the chat groups were lower than at the end of the inpatient treatment, but higher than at admission. During chat aftercare, Activity and Emotional Reactivity scores increased less than during the inpatient phase, but on average Activity and Emotional Reactivity were higher during Internet–chat aftercare. The predictive value of the acquaintance of the therapist from inpatient treatment and the course of group evaluations during inpatient treatment on the course of group evaluations during chat aftercare were examined.

In utero methanesulfonyl fluoride differentially affects learning and maze performance in the absence of long-lasting cholinergic changes in the adult rat

There is increasing evidence that acetylcholinesterase (AChE) may have various specific developmental roles in brain development. Nevertheless, specific effects of AChE inhibition during early brain development have not been adequately described. Therefore, methanesulfonyl fluoride (MSF), an irreversible AChE inhibitor that shows high selectivity for the CNS was used to produce AChE inhibition in utero to study subsequent adult behaviors, sleep, and cholinergic markers. Rats exposed to MSF in utero showed a deficit in spatial learning tasks using appetitive motivation but, surprisingly, they performed equally well or better than controls when aversive motivation was used. One hypothesis was that MSF treatment in utero affected the response to stress. Tests of anxiety however showed no differences in basal levels of anxiety. Studies of sleep behavior, however, indicated a higher level of REM sleep which is only seen during the light phase of male rats exposed to MSF in utero as compared to controls. No differences in cholinergic markers in the brains of adults were found except that females exposed to MSF in utero had a higher level of ChAT activity in the synaptosomal fraction of the hippocampus. Even so, whether cholinergic alterations accompany the in utero MSF exposure remains to be determined. The failure to find widespread changes in cholinergic markers in the adult brains suggests changes in behaviors should be further investigated by testing the participation of postsynaptic mechanisms, measuring of cholinergic markers during earlier development periods and the possible participation of other neurotransmitter systems to clearly reveal the role of the cholinergic system following in utero MSF exposure.

Choline acetyltransferase variants and their influence in schizophrenia and olanzapine response

Choline acetyltransferase (ChAt) is extensively distributed throughout the CNS where, by catalyzing acetylcholine synthesis, it participates in modulating wide-ranging cholinergic-dependent functions including cognitive performance, sleep, arousal, movement, and visual information processing. Recently, compelling evidence has mounted implicating ChAt in schizophrenia. In particular, studies have identified significant reductions in ChAt activity in the nucleus accumbens and pontine tegmentum of such patients, which furthermore correlate significantly with measures of cognitive performance in the disorder. Similarly, elevated levels of choline, the acetylcholine precursor, have been identified among patients, implicating altered ChAt activity in these individuals. We sought to investigate the potential contribution of three ChAt gene polymorphisms in schizophrenia, and uncovered evidence for significant association between one of these, rs1880676G/A, and disease susceptibility among Basque individuals (genotypewise chi(2) = 20.7, P = 0.00003; allelewise chi(2) = 10.1, P = 0.002). A similar trend for association with susceptibility was observed for a second SNP, rs3810950G/A, (genotypwise chi(2) = 6.4, P = 0.05; allelewise chi(2) = 3.75, P = 0.05). Evidence was also uncovered for a potential influence of these polymorphisms on olanzapine treatment outcome among Spanish patients (F-statistic = 5.02, P = 0.03; F-statistic = 6.53, P = 0.02 respectively), and on improvements in positive symptoms in the case of rs3810950 (F-statistic = 5.3, P = 0.03) and general psychopathology in the case of rs1880676 and rs3810950 (F-statistic = 5.24, P = 0.03; F-statistic = 5.31, P = 0.03 respectively) during therapy. While more comprehensive studies are warranted to determine the precise contribution of ChAt mediated mechanisms in schizophrenia, our findings tentatively implicate a genetic influence of ChAt in the disorder's susceptibility and treatment.

Ferulic Acid Supplementation Prevents Trimethyltin-Induced Cognitive Deficits in Mice

This study's objective was to clarify the ameliorative effects ferulic acid (4-hydroxy-3-methoxycinnamic acid) has against cognitive deficits and ChAT activation in trimethyltin (TMT) induced, memory injured mice following a 28-d ferulic acid treatment. After administering TMT for 3 d, each mouse performed Y-maze and passive avoidance tests to check immediate working memory performance and cognitive function. The results showed that ferulic acid administration attenuated TMT-induced memory injury and a decline in ChAT activity in the mice. This suggests that ferulic acid might be useful for preventing cognitive dysfunction as well as for boosting the activation of ChAT in dementia.

Virtual Speakers, Virtual Audiences: Agency, Audience and Constraint in an Online Chat Community

A participant-observer approach was used to explore an online chat community. The chat room was defined in terms of its construction and maintenance of speaker identities, and the user-chat room interface was examined with the aim of exploring how notions of selfhood can be better understood. Chat room audiences were then discussed within the framework of delineating different levels of virtual audiences and outlining processes by which these different levels interact. Finally, formal and informal discursive constraints were explored, and conclusions drawn on the ways that chat room users deal with constraints on their chat activity. Implications for understanding internet communication as well as discourse in general are discussed.

Changes in brain cholinergic markers and spatial learning in old galanin-overexpressing mice

The cholinergic forebrain system is involved in learning and memory, and its age-dependent decline correlates with a decrease in cognitive performance. Since the neuropeptide galanin participates in cholinergic neuron regulation, we have studied 19- to 23-month-old male mice overexpressing galanin under the platelet-derived growth factor B promoter (GalOE) and wild-type (WT) littermates by monitoring behavioral, neurochemical and morphological/histochemical parameters. In the Morris water maze test, old transgenic animals showed a significant impairment in escape latency in the hidden platform test compared to age-matched WT animals. The morphological/histochemical studies revealed that cholinergic neurons in the basal forebrain display a slight, age- but not genotype-related, alteration in choline acetyltransferase- (ChAT) immunoreactivity. The neurochemical studies showed an age-related decline in ChAT activity in the cerebral cortex of all mice, whereas in the hippocampal formation this effect was seen in GalOE but not WT animals. Expression of BDNF mRNA in the hippocampal formation, as evaluated by RT–PCR, was reduced in old animals; no age- or genotype-induced variations in NGF mRNA expression were observed. These data suggest that galanin overexpression further accentuates the age-related decline of the cholinergic system activity in male mice, resulting in impairment of water maze performance in old animals.

Regulation of self-incompatibility by acetylcholine and cAMP in Lilium longiflorum

Elongation of pollen tubes in pistils of Lilium longiflorum cv. Hinomoto after self-incompatible pollination was here found to be promoted by acetylcholine (ACh) and other choline derivatives, such as acetylthiocholine, l-alpha-phosphatidylcholine and chlorocholinechloride [CCC; (2-chloroethyl) trimethyl ammonium chloride]. Moreover, the elongation was promoted by neostigmine, a potent inhibitor of acetylcholinesterase (AChE; acetylcholine-decomposing enzyme) (EC 3.1.1.7.) and activities of this and choline acetyltransferase (ChAT; acetylcholine-forming enzyme) (EC 2.3.1.6.) in pistils were associated with self-incompatibility. The activity of ChAT was lower after self-incompatible as compared with cross-compatible pollination. Application of cAMP promoted ChAT activities in both cases, whereas activity of AChE in pistils after self-pollination was higher than that after cross-compatible pollination and was suppressed by cAMP in both cases. Furthermore, AChE activity was inhibited by treatment with neostigmine or heating. Our results indicate that the self-incompatibility with self-pollination is due to decrease of ACh and cAMP, causing reduction of ChAT and AC (adenylate cyclase) and concise elevation of AChE and PDE (cAMP phosphodiesterase), and therefore suppressed growth of pollen tubes.

Experimental study on diagnosing the brachial plexus injury through quickly detecting the ChAT activity

目的 寻找一种简单快速、能在手术中准确客观地判断臂丛损伤神经残端功能的方法.方法选用成年雌性SD大鼠45只,随机分成两组,分别制成臂丛节前和节后损伤的动物模型,采用放射性同位素的方法测定损伤后不同时间臂丛神经中胆碱乙酰基转移酶(choline acetyltransferase,ChAT)的活性,然后用统计学的方法总结其中规律.结果节前、节后两种损伤类型胆碱乙酰基转移酶的活性均随时间降低,节前组ChAT活性随时间迅速降低,很快达到正常活性的1/10(675±258)cpm;节后组ChAT活性随时间缓慢降低,90d后只降低到正常活性的1/2(4906±1119)cpm.结论术中快速测定ChAT的活性可以用来定量地区分臂丛损伤后的神经残端功能,以判定残端的可利用性。

Promotional Chat on the Internet

Chat rooms, recommendation sites, and customer review sections allow consumers to overcome geographic boundaries and to communicate based on mutual interests. However, marketers also have incentives to supply promotional chat or reviews in order to influence the consumers’ evaluation of their products. Moreover, firms can disguise their promotion as consumer recommendations due to the anonymity afforded by online communities. We explore this new setting where advertising and word of mouth become perfect substitutes because they appear indistinguishable to the consumer. Specifically, we investigate here whether word of mouth remains credible and whether firms choose to devote more resources promoting their inferior or superior products. We develop a game theoretic model in which two products are differentiated in their value to the consumer. Unlike the firms, the consumers are uncertain about the products’ quality. The consumers read messages online that help them decide on the identity of the superior product. We find a unique equilibrium where online word of mouth is persuasive despite the promotional chat activity by competing firms. In this equilibrium, firms spend more resources promoting inferior products, in striking contrast to existing advertising literature. In addition, we discuss consumer welfare implications and how other marketing strategies might interact with promotional chat.

Language learning

Language learning

The Use of L1 in an L2 On-Line Chat Activity

This study focuses on the use of the native language (L1) by second language (L2) learners when carrying out a collaborative jigsaw task in a computer chat environment. It investigates the extent and function of L1 use by means of a sociocultural theoretical framework. The research project was carried out in three languages: Chinese, German, and Spanish. Students were assigned to dyads at random and were asked to perform a jigsaw task activity. The chat logs were collected and analyzed via descriptive statistics and discourse analysis. The findings suggest that across all three languages, the students used their L1 (English) to varying degrees and for a variety of functions. ‘Moving the task along’ (Swain &amp; Lapkin, 2000a) was the primary function of the L1. Further examination of the chat logs indicates that several factors affected the use of L1, such as participants' task management strategies and the use of symbols.

Low molecular weight glycosaminoglycan C3 attenuates AF64A-stimulated, low-affinity nerve growth factor receptor-immunoreactive axonal varicosities in the rat septum

Glycosaminoglycans (GAGs) play a pivotal role in the pathogenesis of Alzheimer's disease (AD). Although, as we have shown earlier, a low molecular weight GAG, C3, protects against ethylcholine aziridinium (AF64A)-induced cholinergic damage, and against Aβ-induced tau-2-immunoreactivity (IR), the mechanism of the neuroprotective effect of GAGs is not yet known. Several clues exist. Previous studies in rats revealed that continuous NGF infusion (icv) after AF64A injection increases septal ChAT and AChE activities. Moreover, C3 increases axonal outgrowth in the rat hippocampus, raising the possibility of a NGF-receptor mediated neuroprotection. Furthermore, it has been reported that NGF expression is increased in the septum following AF64A administration. To study the question regarding the mechanism of neuroprotective action of GAGs, AF64A, a selective cholinotoxin, was administered stereotaxically, bilaterally, into the lateral ventricles of Fischer albino male rats (1 nmol/2 μl/side). In order to establish the effect of C3 on the expression of the NGF receptor-IR elements, C3 was administered orally (25 mg/kg, once a day), by gavage, 7 days before, and 7 days after the AF64A injection. NGF receptor immunohistochemistry revealed that AF64A induced the appearance of NGF-receptor-IR axonal varicosities in the rat medial septum. These varicose fibers were attenuated by 14 days' administration of C3. The possible explanation of our data may be that C3 increases NGF synthesis in the lateral septum. The increased level of NGF could suppress the increased, AF64A-induced NGF receptor expression in the medial septal nucleus. These results further accentuate our earlier observations that C3 may have potential as a therapeutic agent in AD and other neurodegenerative disorders.

The Use of L1 in an L2 On-Line Chat Activity

The Use of L1 in an L2 On-Line Chat Activity

The effect of acupuncture on the NO activity and cholinergic systerm in brain of Alzheimer's disease rats

目的 探讨针刺对拟Alzheimer's Disease(AD)大鼠大脑一氧化氮(NO)活性和皮质、海马胆碱能系统功能的影响.方法用迷宫试验观测针刺对拟AD大鼠学习记忆能力的影响;采用硝酸还原酶法测定NO含量;应用巯基比色分析法、免疫组化法测定大鼠海马区乙酰胆碱酯酶(AchE)和胆碱乙酰化酶(ChAT)活性变化.结果针刺组走完迷宫全程时间(150.22±12.47)秒与模型组(232.00±15.56)秒比较,存在显著性差异(P＜0.01);针刺组走迷宫走错次数(3.00±0.24)次与模型组(4.38±0.26)次比较,具有显著性差异(P＜0.01);针刺组大脑皮质NO含量(64.75±6.01)μmol/L比模型组(111.80±8.90)μmol/L显著降低(P＜0.01);针刺组AchE活性(3.73±0.22)μmol/ml比模型组(2.35±0.33)μmol/ml明显增强(P＜0.01),针刺组ChAT活性(PU值20.00±1.00)与模型组(PU值13.86±1.04)相比明显升高(P＜0.01).结论 针刺可减少中枢NO的合成,从而减轻对大脑的神经毒作用;同时可提高中枢胆碱能系统功能,缓解拟AD大鼠的学习记忆障碍。

Dose-Dependent Neurochemical and Functional Protection Afforded by Encapsulated CNTF-Producing Cells

Intracerebral delivery of hCNTF has shown considerable neuroprotective potential in animal models of Huntington's disease (HD). The present study describes the relationship between a range of hCNTF doses and the resulting behavioral and neurochemical (striatal ChAT and GAD activity) protection in a rodent model of HD. Encapsulated BHK delivering a range of hCNTF doses were implanted into the lateral ventricle ipsilateral to an intrastriatal quinolinic acid (QA) injection. Results demonstrated a dose-dependent effect of hCNTF with complete, partial, and no observable neuroprotection occurring with preimplant doses of hCNTF of 30.8, 8.6, and 0.8-2.1 ng hCNTF/24 h, respectively. These data continue to support the use of cellular delivery of hCNTF for HD and will facilitate the optimization of this approach in the clinical situation.