Receptors & channels最新文献_第4页

Immunocytochemical Study of α 1 and β 2/3 Subunits of GABA A Receptors in Freehand Isolated Vestibular Deiters' Neurons 手离体前庭神经元GABA A受体α 1和β 2/3亚基的免疫细胞化学研究

Receptors & channels Pub Date : 2003-01-01 DOI: 10.3109/10606820308247

M. V. Rapallino, A. Cupello, C. Luccardini, E. Nieddu, A. Seitun, M. Robello

{"title":"Immunocytochemical Study of α 1 and β 2/3 Subunits of GABA A Receptors in Freehand Isolated Vestibular Deiters' Neurons","authors":"M. V. Rapallino, A. Cupello, C. Luccardini, E. Nieddu, A. Seitun, M. Robello","doi":"10.3109/10606820308247","DOIUrl":"https://doi.org/10.3109/10606820308247","url":null,"abstract":": Vestibular Deiters' neurons have been isolated from bovine brain by the Hyden's freehand dissection technique and challenged with monoclonal antibodies directed toward the alpha 1 and beta 2/3 subunits of the GABAA receptors. Subsequent challenge with fluorescent secondary antibodies and confocal microscopy allowed the study of the cellular distribution of such subunits. In Deiters' neurons the beta 2/3 subunit displayed a clear presence all along the cell body profile and the initial parts of the dendrites. The alpha 1 subunit was found highly present all over the cell interior except the nuclear profiles. The strong presence inside the cells possibly masked its presence on the plasma membrane. However, in part of the cells studied a distinct presence on the plasma membrane was evident. This subunit was visualized also all along the long dendrites of these neurons. The approach we describe here, involving freehand isolated mature neurons from adult animals, may allow a better characterization of the tridimensional distribution of different types of neuronal GABAA receptors in the respect of the approach with brain slices.","PeriodicalId":20928,"journal":{"name":"Receptors & channels","volume":"22 1","pages":"77-81"},"PeriodicalIF":0.0,"publicationDate":"2003-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79000306","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Stoichiometry of recombinant heteromeric glycine receptors revealed by a pore-lining region point mutation. 由孔衬区点突变揭示的重组异聚甘氨酸受体的化学计量学。

Receptors & channels Pub Date : 2003-01-01 DOI: 10.3109/714041016

Valeria Burzomato, Paul J Groot-Kormelink, Lucia G Sivilotti, Marco Beato

{"title":"Stoichiometry of recombinant heteromeric glycine receptors revealed by a pore-lining region point mutation.","authors":"Valeria Burzomato, Paul J Groot-Kormelink, Lucia G Sivilotti, Marco Beato","doi":"10.3109/714041016","DOIUrl":"10.3109/714041016","url":null,"abstract":"Heteromeric glycine receptors mediate synaptic inhibition in the caudal areas of the adult mammalian central nervous system (CNS). These channels resemble other receptors in the nicotinic superfamily in that they are pentamers, but may differ in that they contain alpha and beta subunits in a 3:2 rather than a 2:3 ratio. Evidence in favor of a 3alpha:2beta stoichiometry of heteromeric glycine receptors comes from biochemical data and from the expression of chimeric subunits. We investigated this question using a potentially more direct approach and mutated the highly conserved hydrophobic residues in the middle (position 9') of the pore-lining domain. This mutation increases agonist potency in all channels in the nicotinic superfamily and its effects are in first approximation proportional to the number of mutant subunit incorporated into the receptor. We expressed in HEK 293 cells wild-type glycine alpha1beta receptors or receptors bearing the 9' mutation on either the alpha or the beta subunit, using an alpha:beta plasmid ratio of 1:40 in the transfection. This resulted in negligible levels of contamination by homomeric alpha1 receptors, as proven by low picrotoxin potency and by the extreme rarity of high conductances in single channel recording. Our data show that the effects of the 9' mutation on the receptor sensitivity to glycine were more marked when the alpha subunit bore the mutation. The magnitude of the leftward shift in the agonist dose-response curve for the two mutant combinations was in agreement with a subunit stoichiometry of 3alpha:2beta.","PeriodicalId":20928,"journal":{"name":"Receptors & channels","volume":"9 6","pages":"353-61"},"PeriodicalIF":0.0,"publicationDate":"2003-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"24143719","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Stable expression and characterization of human PN1 and PN3 sodium channels. 人PN1和PN3钠通道的稳定表达和表征。

Receptors & channels Pub Date : 2003-01-01 DOI: 10.3109/713745174

Isamu Akiba, Tetsuo Seki, Masayuki Mori, Masaki Iizuka, Seiichiro Nishimura, Sachie Sasaki, Keiji Imoto, Edward L Barsoumian

{"title":"Stable expression and characterization of human PN1 and PN3 sodium channels.","authors":"Isamu Akiba, Tetsuo Seki, Masayuki Mori, Masaki Iizuka, Seiichiro Nishimura, Sachie Sasaki, Keiji Imoto, Edward L Barsoumian","doi":"10.3109/713745174","DOIUrl":"https://doi.org/10.3109/713745174","url":null,"abstract":"Nociceptive transduction in inflammatory and neuropathic pain involves peripherally expressed voltage-gated sodium channels, such as tetrodotoxin (TTX)-sensitive PN1 and TTX-resistant PN3. We generated recombinant cell lines stably expressing the human PN1 and PN3 sodium channels in Chinese hamster ovary (CHO) cells using inducible expression vectors. The PN1 and PN3 cDNAs were isolated from human adrenal gland and heart poly(A)+ RNAs, respectively. The recombinant human PN1 currents exhibited rapid activation and inactivation kinetics and were blocked by TTX with a half-maximal inhibitory concentration (IC50) of 32.6 nM. The human PN3 channel expressed in stable transfectants showed TTX-resistant inward currents with slow inactivation kinetics. The IC50 value for TTX was 73.3 microM. The voltage-dependence of activation of the PN3 channel was shifted to the depolarizing direction, compared to that of the PN1 channel. Lidocaine and mexiletine exhibited tonic and use-dependent block of PN1 and PN3 channels. The PN1 channel was more susceptible to inhibition by mexiletine than PN3. These results suggest that stable transfectants expressing the human PN1 and PN3 sodium channels will be useful tools to define subtype selectivity for sodium channel blockers.","PeriodicalId":20928,"journal":{"name":"Receptors & channels","volume":"9 5","pages":"291-9"},"PeriodicalIF":0.0,"publicationDate":"2003-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3109/713745174","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"24013765","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 18

The effects of flumazenil on the antinociceptive actions of morphine in rats. 氟马西尼对大鼠吗啡抗感觉作用的影响。

Receptors & channels Pub Date : 2003-01-01 DOI: 10.3109/713745175

Joseph R Holtman, Xin Jing, Jewell W Sloan, Elzbieta P Wala

引用次数: 4

Cellular signaling mechanisms for muscarinic acetylcholine receptors. 毒蕈碱乙酰胆碱受体的细胞信号传导机制。

Receptors & channels Pub Date : 2003-01-01

A A Lanzafame, A Christopoulos, F Mitchelson

{"title":"Cellular signaling mechanisms for muscarinic acetylcholine receptors.","authors":"A A Lanzafame, A Christopoulos, F Mitchelson","doi":"","DOIUrl":"","url":null,"abstract":"Signaling pathways for muscarinic acetylcholine receptors (mAChRs) include several enzymes and ion channels. Recent studies have revealed the importance of various isoforms of both alpha and betagamma subunits of G proteins in initiation of signaling as well as the role of the small monomeric G protein, Rho, in the activation of phospholipase D. Modulation of adenylyl cyclase activity by mAChRs appears more diverse as the interaction of various receptor subtypes with the many isoforms of the enzyme are studied. Both alpha and beta subunits of G(i/o) may be involved. Some mAChR responses arise through release of nitric oxide from nitrergic nerves, including salivary gland secretion and hippocampal slow wave activity. mAChRs utilize a variety of intracellular pathways to activate various mitogen-activated protein kinases. The kinases are involved in cholinergic regulation of kidney epithelial function, catabolism of amyloid precursor protein, hippocampal long-term potentiation, activation of phospholipase A(2), and gene induction. mAChR activation can also stimulate or inhibit cellular growth and apoptosis, dependent on prior levels of cellular activity. Modulation of ion channels by mAChR agonists appears increasingly complex, based on recent studies. K(+) channels may be activated by M(2) and M(4) mAChR stimulation, although in the rat superior cervical ganglion topographical constraints appear to limit the effect to the M(2) mAChR. Another ganglionic K(+) current, the M current, is inhibited by M(1) mAChR activation, but in murine hippocampus inhibition involves another receptor subtype. R-type Ca(2+) channels are both facilitated and inhibited by M(1) and M(2) mAChRs; facilitation being more pronounced with activation of M(1) mAChRs and inhibition with M(2) mAChRs.","PeriodicalId":20928,"journal":{"name":"Receptors & channels","volume":"9 4","pages":"241-60"},"PeriodicalIF":0.0,"publicationDate":"2003-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"22509790","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

M1-M5 muscarinic receptor knockout mice as novel tools to study the physiological roles of the muscarinic cholinergic system. M1-M5毒蕈碱受体敲除小鼠作为研究毒蕈碱胆碱能系统生理作用的新工具。

Receptors & channels Pub Date : 2003-01-01

J Wess, A Duttaroy, W Zhang, J Gomeza, Y Cui, T Miyakawa, F P Bymaster, L McKinzie, C C Felder, K G Lamping, F M Faraci, C Deng, M Yamada

{"title":"M1-M5 muscarinic receptor knockout mice as novel tools to study the physiological roles of the muscarinic cholinergic system.","authors":"J Wess, A Duttaroy, W Zhang, J Gomeza, Y Cui, T Miyakawa, F P Bymaster, L McKinzie, C C Felder, K G Lamping, F M Faraci, C Deng, M Yamada","doi":"","DOIUrl":"","url":null,"abstract":"A large body of evidence indicates that muscarinic acetylcholine receptors (mAChRs) play critical roles in regulating the activity of many important functions of the central and peripheral nervous systems. However, identification of the physiological and pathophysiological roles of the individual mAChR subtypes (M(1)-M(5)) has proven a difficult task, primarily due to the lack of ligands endowed with a high degree of receptor subtype selectivity and the fact that most tissues and organs express multiple mAChRs. To circumvent these difficulties, we used gene targeting technology to generate mutant mouse lines containing inactivating mutations of the M(1)-M(5) mAChR genes. The different mAChR mutant mice and the corresponding wild-type control animals were subjected to a battery of physiological, pharmacological, behavioral, biochemical, and neurochemical tests. The M(1)-M(5) mAChR mutant mice were viable and reproduced normally. However, each mutant line displayed specific functional deficits, suggesting that each mAChR subtype mediates distinct physiological functions. These results should offer new perspectives for the rational development of novel muscarinic drugs.","PeriodicalId":20928,"journal":{"name":"Receptors & channels","volume":"9 4","pages":"279-90"},"PeriodicalIF":0.0,"publicationDate":"2003-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"22510913","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

High throughput electrophysiology: new perspectives for ion channel drug discovery. 高通量电生理学:离子通道药物发现的新视角。

Receptors & channels Pub Date : 2003-01-01

Niels J Willumsen, Morten Bech, Søren-Peter Olesen, Bo Skaaning Jensen, Mads P G Korsgaard, Palle Christophersen

{"title":"High throughput electrophysiology: new perspectives for ion channel drug discovery.","authors":"Niels J Willumsen, Morten Bech, Søren-Peter Olesen, Bo Skaaning Jensen, Mads P G Korsgaard, Palle Christophersen","doi":"","DOIUrl":"","url":null,"abstract":"Proper function of ion channels is crucial for all living cells. Ion channel dysfunction may lead to a number of diseases, so-called channelopathies, and a number of common diseases, including epilepsy, arrhythmia, and type II diabetes, are primarily treated by drugs that modulate ion channels. A cornerstone in current drug discovery is high throughput screening assays which allow examination of the activity of specific ion channels though only to a limited extent. Conventional patch clamp remains the sole technique with sufficiently high time resolution and sensitivity required for precise and direct characterization of ion channel properties. However, patch clamp is a slow, labor-intensive, and thus expensive, technique. New techniques combining the reliability and high information content of patch clamping with the virtues of high throughput philosophy are emerging and predicted to make a number of ion channel targets accessible for drug screening. Specifically, genuine HTS parallel processing techniques based on arrays of planar silicon chips are being developed, but also lower throughput sequential techniques may be of value in compound screening, lead optimization, and safety screening. The introduction of new powerful HTS electrophysiological techniques is predicted to cause a revolution in ion channel drug discovery.","PeriodicalId":20928,"journal":{"name":"Receptors & channels","volume":"9 1","pages":"3-12"},"PeriodicalIF":0.0,"publicationDate":"2003-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"22453415","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

High throughput electrophysiology using a fully automated, multiplexed recording system. 高通量电生理使用全自动，多路记录系统。

Receptors & channels Pub Date : 2003-01-01

Jonathan D Trumbull, Eugene S Maslana, David G McKenna, Thomas A Nemcek, Wende Niforatos, Jeffrey Y Pan, Ashutosh S Parihar, Char-Chang Shieh, Julie A Wilkins, Clark A Briggs, Daniel Bertrand

{"title":"High throughput electrophysiology using a fully automated, multiplexed recording system.","authors":"Jonathan D Trumbull, Eugene S Maslana, David G McKenna, Thomas A Nemcek, Wende Niforatos, Jeffrey Y Pan, Ashutosh S Parihar, Char-Chang Shieh, Julie A Wilkins, Clark A Briggs, Daniel Bertrand","doi":"","DOIUrl":"","url":null,"abstract":"The drug discovery process centers around finding and optimizing novel compounds active at therapeutic targets. This process involves direct and indirect measures of how compounds affect the behavior of the target in question. The sheer number of compounds that must be tested poses problems for classes of ion channel targets for which direct functional measurements (e.g., traditional patch-clamping) are too cumbersome and indirect measurements (e.g., Ca(2+)-sensitive dyes) lack sufficient sensitivity or require unacceptable compromises. We present an optimized process for obtaining large numbers of direct electrophysiological measurements (two-electrode voltage-clamp) from Xenopus oocytes using a combination of automated oocyte handling, efficient and flexible liquid delivery, parallel operation, and powerful integrated data analysis. These improvements have had a marked impact, increasing the contribution electrophysiology makes in optimizing lead compound series and the discovery of new ones. The design of the system is detailed along with examples of data generated in support of lead optimization and discovery.","PeriodicalId":20928,"journal":{"name":"Receptors & channels","volume":"9 1","pages":"19-28"},"PeriodicalIF":0.0,"publicationDate":"2003-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"22453417","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Putative dynamics of vasopressin in its V1a receptor binding site. 抗利尿激素在其V1a受体结合位点的推测动力学。

Receptors & channels Pub Date : 2003-01-01 DOI: 10.3109/10606820308251

A. Kaltenböck, M. Hibert, T. Langer

{"title":"Putative dynamics of vasopressin in its V1a receptor binding site.","authors":"A. Kaltenböck, M. Hibert, T. Langer","doi":"10.3109/10606820308251","DOIUrl":"https://doi.org/10.3109/10606820308251","url":null,"abstract":"The molecular architecture of the GPCRs, including the dynamic set of interactions between the receptor and the ligand, is one of the key structural questions of biophysical approaches. In the present study, molecular dynamics (MD) simulations were performed on the well-validated molecular model of the vasopressin V1a receptor applying different parameters (i.e., force fields, time variation, use of constraints) in order to sample the conformational space of the endogenous ligand arginine vasopressin (AVP), to explore different putative binding modes, and to analyze the simulation results with respect to experimental data. Noteworthy, it is to mention that for the first time a model of the vasopressin receptor remained stable in a 500 ps MD simulation run under vacuo boundary conditions using the Kollman all-atom FF even though no constraints were imposed. Conclusively, we determined an optimized experimental procedure for studying the dynamics and structure-functionship of this highly important family of GPCRs: the use of MD simulations with the Kollman all-atom force-field parameters on a constrained receptor. Our simplified model may be used as a basis for structure based design of new GPCR ligands and for in silico screening of virtual combinatorial chemistry libraries.","PeriodicalId":20928,"journal":{"name":"Receptors & channels","volume":"22 1","pages":"93-106"},"PeriodicalIF":0.0,"publicationDate":"2003-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75232099","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Genetic approaches to visual transduction in Drosophila melanogaster. 黑腹果蝇视觉转导的遗传研究。

Receptors & channels Pub Date : 2003-01-01 DOI: 10.3109/10606820308242

W. Pak, H. Leung

{"title":"Genetic approaches to visual transduction in Drosophila melanogaster.","authors":"W. Pak, H. Leung","doi":"10.3109/10606820308242","DOIUrl":"https://doi.org/10.3109/10606820308242","url":null,"abstract":"Because almost everything we know about Drosophila phototransduction has come from studies based on genetic approaches, this review begins with a discussion of genetic approaches. We then present a brief overview of Drosophila phototransduction (section on Drosophila phototransduction: an overview) followed by a more detailed treatment of individual components of the transduction machinery (section on Components of the phototransduction machinery). Discussion of transduction mechanisms is presented under three headings: Mechanism(s) of channel excitation, Organization of the transduction proteins, and Regulatory mechanisms in phototransduction. Perhaps the most important unanswered question in this field is the mechanism(s) of activation and regulation of transduction channels. This question is explored in the section entitled Mechanism(s) of channel excitation. Identification of at least two of the proteins discussed was totally unexpected: the rhodopsin chaperone protein, ninaA, and the signal complex scaffold protein, INAD. They are discussed in the sections titled Requirement for a chaperone protein for Rh1 opsin, and: Formation of signaling complexes, respectively. One of the important developments in this field has been the discovery of mammalian homologs of many of the proteins identified in Drosophila. A brief discussion of the most extensively studied of these, the mammalian homologs of light-activated channel protein, trp, is presented in the section on Mammalian Homologs of trp. We conclude the review with Perspective, a brief look at the current status and the future outlook of the field.","PeriodicalId":20928,"journal":{"name":"Receptors & channels","volume":"27 1","pages":"149-67"},"PeriodicalIF":0.0,"publicationDate":"2003-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90341085","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 43