Millipore Sigma Vibrant Logo
 

acetylcholine+receptor


409 Results Advanced Search  
Showing

Narrow Your Results Use the filters below to refine your search

Document Type

  • (191)
  • (170)
  • (8)
Can't Find What You're Looking For?
Contact Customer Service

 
  • Nicotinic acetylcholine receptor subunit mRNA expression and channel function in medial habenula neurons. 11044729

    Relationships between nicotinic acetylcholine receptor (nAChR) channel function and nAChR subunit mRNA expression were explored in acutely isolated rat medial habenula (MHb) neurons using a combination of whole-cell recording and single cell RT-PCR techniques. Following amplification using subunit-specific primers, subunits could be categorized in one of three ways: (i) present in 95-100% cells: alpha3, alpha4, alpha5, beta2 and beta4; (ii) never present: alpha2; and (iii) sometimes present ( approximately 40% cells): alpha6, alpha7 and beta3. These data imply that alpha2 subunits do not participate in nAChRs on MHb cells, that alpha6, alpha7 and beta3 subunits are not necessary for functional channels but may contribute in some cells, and that nAChRs may require combinations of all or subsets of alpha3, alpha4, alpha5, beta2 and beta4 subunits. Little difference in the patterns of subunit expression between nicotine-sensitive and insensitive cells were revealed based on this qualitative analysis, implying that gene transcription per se may be an insufficient determinant of nAChR channel function. Normalization of nAChR subunit levels to the amount of actin mRNA, however, revealed that cells with functional channels were associated with high levels (>0.78 relative to actin; 11/12 cells) of all of the category (i) subunits: alpha3, alpha4, alpha5, beta2 and beta4. Conversely, one or more of these subunits was always low (0.40 relative to actin) in all cells with no detectable response to nicotine. Thus the formation of functional nAChR channels on MHb cells may require critical levels of several subunit mRNAs.
    Document Type:
    Reference
    Product Catalog Number:
    MAB305
    Product Catalog Name:
    Anti-Choline Acetyltransferase Antibody, clone 1E6
  • Acetylcholine and histamine are transmitter candidates in identifiable mechanosensitive neurons of the spider Cupiennius salei: an immunocytochemical study. 8995212

    Histochemical and indirect immunocytochemical techniques were used to search for neuroactive substances and transmitter candidates in identified sensory neurons of two types of cuticular mechanoreceptors in the spider Cupiennius salei Keys.: (1) in lyriform slit-sense organ VS-3 (comprising 7-8 cuticular slits each innervated by 2 bipolar neurons), and (2) in tactile hairs (each supplied by 3 bipolar sensory cells). All neurons are mechanosensitive. A polyclonal antibody against choline acetyltransferase (ChAT) strongly labeled all cell bodies and afferent fibers of both mechanoreceptor types. Western blot analysis using the same antibody against samples of spider sensory hypodermis and against samples from the central nervous system demonstrated a clear band at 65 kDa, corresponding to the molecular mass of ChAT in insects. Moreover, staining for acetylcholine esterase (AChE) revealed AChE activity in one neuron of each mechanoreceptor type. Incubation with a polyclonal antibody against histamine clearly labeled one neuron in each set of sensilla, whereas activity in the remaining one or two cells was near background. All mechanoreceptor preparations treated with a polyclonal antiserum against serotonin tested negative, whereas sections through the central nervous system of the same spiders were clearly labeled for serotonin. The presence of ChAT-like immunoreactivity and AChE implicates acetylcholine as a transmitter candidate in the two mechanoreceptive organs. We assume that histamine serves as a mechanosensory co-transmitter in the central nervous system and may also act at peripheral synapses that exist in these sensilla.
    Document Type:
    Reference
    Product Catalog Number:
    AB143
    Product Catalog Name:
    Anti-Choline Acetyltransferase (ChAT) Antibody
  • Muscarinic acetylcholine receptor localization and activation effects on ganglion response properties. 20042645

    PURPOSE: The activation and blockade of muscarinic acetylcholine receptors (mAChRs) affects retinal ganglion cell light responses and firing rates. This study was undertaken to identify the full complement of mAChRs expressed in the rabbit retina and to assess mAChR distribution and the functional effects of mAChR activation and blockade on retinal response properties. METHODS: RT-PCR, Western blot analysis, and immunohistochemistry were used to identify the complement and distribution of mAChRs in the rabbit retina. Extracellular electrophysiology was used to determine the effects of the activation or blockade of mAChRs on ganglion cell response properties. RESULTS: RT-PCR of whole neural retina resulted in the amplification of mRNA transcripts for the m1 to m5 mAChR subtypes. Western blot and immunohistochemical analyses confirmed that all five mAChR subtypes were expressed by subpopulations of bipolar, amacrine, and ganglion cells in the rabbit retina, including subsets of cells in cholinergic and glycinergic circuits. Nonspecific muscarinic activation and blockade resulted in the class-specific modulation of maintained ganglion cell firing rates and light responses. CONCLUSIONS: The expression of mAChR subtypes on subsets of bipolar, amacrine, and ganglion cells provides a substrate for both enhancement and suppression of retinal responses via activation by cholinergic agents. Thus, the muscarinic cholinergic system in the retina may contribute to the modulation of complex stimuli. Understanding the distribution and function of mAChRs in the retina has the potential to provide important insights into the visual changes that are caused by decreased ACh in the retinas of Alzheimer\'s patients and the potential visual effects of anticholinergic treatments for ocular diseases.
    Document Type:
    Reference
    Product Catalog Number:
    Multiple
    Product Catalog Name:
    Multiple
  • Alpha7 nicotinic acetylcholine receptor expression by vascular smooth muscle cells facilitates the deposition of Abeta peptides and promotes cerebrovascular amyloid angio ... 18708033

    Deposition of beta-amyloid (Abeta) peptides in the walls of brain blood vessels, cerebral amyloid angiopathy (CAA), is common in patients with Alzheimer's disease (AD). Previous studies have demonstrated Abeta peptide deposition among vascular smooth muscle cells (VSMCs), but the source of the Abeta and basis for its selective deposition in VSMCs are unknown. In the present study, we examined the deposition patterns of Abeta peptides, Abeta40 and Abeta42, within the cerebrovasculature of AD and control patients using single- and double-label immunohistochemistry. Abeta40 and Abeta42 were abundant in VSMCs, especially in leptomeningeal arteries and their initial cortical branches; in later-stage AD brains this pattern extended into the microvasculature. Abeta peptide deposition was linked to loss of VSMC viability. Perivascular leak clouds of Abeta-positive material were associated primarily with arterioles. By contrast, control brains possessed far fewer Abeta42- and Abeta40-immunopositive blood vessels, with perivascular leak clouds of Abeta-immunopositive material rarely observed. We also demonstrate that VSMCs in brain blood vessels express the alpha7 nicotinic acetylcholine receptor (alpha7nAChR), which has high binding affinity for Abeta peptides, especially Abeta42. These results suggest that the blood and blood-brain barrier permeability provide a major source of the Abeta peptides that gradually deposit in brain VSMCs, and the presence and abundance of the alpha7nAChR on VSMCs may facilitate the selective accumulation of Abeta peptides in these cells.
    Document Type:
    Reference
    Product Catalog Number:
    AB5078P
    Product Catalog Name:
    Anti-Beta-Amyloid 1-42 Antibody
  • Alpha7 nicotinic acetylcholine receptor is required for blood-brain barrier injury-related CNS disorders caused by Cryptococcus neoformans and HIV-1 associated comorbidit ... 26285576

    Cryptococcal meningitis is the most common fungal infection of the central nervous system (CNS) in HIV/AIDS. HIV-1 virotoxins (e.g., gp41) are able to induce disorders of the blood-brain barrier (BBB), which mainly consists of BMEC. Our recent study suggests that α7 nAChR is an essential regulator of inflammation, which contributes to regulation of NF-κB signaling, neuroinflammation and BBB disorders caused by microbial (e.g., HIV-1 gp120) and non-microbial [e.g., methamphetamine (METH)] factors. However, the underlying mechanisms for multiple comorbidities are unclear.In this report, an aggravating role of α7 nAChR in host defense against CNS disorders caused by these comorbidities was demonstrated by chemical [inhibitor: methyllycaconitine (MLA)] and genetic (α7(-/-) mice) blockages of α7 nAChR.As shown in our in vivo studies, BBB injury was significantly reduced in α7(-/-) mice infected with C. neoformans. Stimulation by the gp41 ectodomain peptide (gp41-I90) and METH was abolished in the α7(-/-) animals. C. neoformans and gp41-I90 could activate NF-κB. Gp41-I90- and METH-induced monocyte transmigration and senescence were significantly inhibited by MLA and CAPE (caffeic acid phenethyl ester, an NF-κB inhibitor).Collectively, our data suggest that α7 nAChR plays a detrimental role in the host defense against C. neoformans- and HIV-1 associated comorbidity factors-induced BBB injury and CNS disorders.
    Document Type:
    Reference
    Product Catalog Number:
    07-212
    Product Catalog Name:
    Anti-dimethyl-Histone H3 (Lys9) Antibody
  • Functional nicotinic acetylcholine receptors containing α6 subunits are on GABAergic neuronal boutons adherent to ventral tegmental area dopamine neurons. 21325521

    Diverse nicotinic acetylcholine receptor (nAChR) subtypes containing different subunit combinations can be placed on nerve terminals or soma/dendrites in the ventral tegmental area (VTA). nAChR α6 subunit message is abundant in the VTA, but α6*-nAChR cellular localization, function, pharmacology, and roles in cholinergic modulation of dopaminergic (DA) neurons within the VTA are not well understood. Here, we report evidence for α6β2*-nAChR expression on GABA neuronal boutons terminating on VTA DA neurons. α-Conotoxin (α-Ctx) MII labeling coupled with immunocytochemical staining localizes putative α6*-nAChRs to presynaptic GABAergic boutons on acutely dissociated, rat VTA DA neurons. Functionally, acetylcholine (ACh) induces increases in the frequency of bicuculline-, picrotoxin-, and 4-aminopyridine-sensitive miniature IPSCs (mIPSCs) mediated by GABA(A) receptors. These increases are abolished by α6*-nAChR-selective α-Ctx MII or α-Ctx PIA (1 nm) but not by α7 (10 nm methyllycaconitine) or α4* (1 μm dihydro-β-erythroidine)-nAChR-selective antagonists. ACh also fails to increase mIPSC frequency in VTA DA neurons prepared from nAChR β2 knock-out mice. Moreover, ACh induces an α-Ctx PIA-sensitive elevation in intraterminal Ca(2+) in synaptosomes prepared from the rat VTA. Subchronic exposure to 500 nm nicotine reduces ACh-induced GABA release onto the VTA DA neurons, as does 10 d of systemic nicotine exposure. Collectively, these results indicate that α6β2*-nAChRs are located on presynaptic GABAergic boutons within the VTA and modulate GABA release onto DA neurons. These presynaptic α6β2*-nAChRs likely play important roles in nicotinic modulation of DA neuronal activity.
    Document Type:
    Reference
    Product Catalog Number:
    Multiple
    Product Catalog Name:
    Multiple
  • Increase of acetylcholine release by Panax ginseng root enhances insulin secretion in Wistar rats. 17123721

    The present study was designed to ascertain the effect of Panax ginseng root on plasma glucose and investigate the possible mechanisms for the effect. Ninety minutes after the oral administration of P. ginseng root to fasting Wistar rats, plasma glucose decreased in a dose-dependent manner. Simultaneous with the reduction in plasma glucose, an increase in the plasma level of insulin and C-peptide was also observed. Moreover, disruption of the available synaptic acetylcholine (ACh), using the inhibitor for choline uptake (hemicholinium-3), or the inhibitor for vesicular choline transport (vesamicol), abolished the metabolic actions of P. ginseng root. Conversely, physostigmine, at a concentration sufficient to inhibit acetylcholinesterase, enhanced the metabolic effect of P. ginseng root. It is possible that P. ginseng root mediates the release of ACh from nerve terminals to enhance insulin secretion. Blockade of the actions of P. ginseng root by 4-diphenylacetoxy-N-methylpiperdine methiodide (4-DAMP) suggested that the site of action is the muscarinic M(3) receptor. Taken together, the results suggest that P. ginseng root has the ability to increase the release of ACh from nerve terminals in rats so as to stimulate muscarinic M(3) receptors activity located in the pancreatic cells for the secretion of insulin, which in turn lower plasma glucose.
    Document Type:
    Reference
    Product Catalog Number:
    EZRMI-13K
    Product Catalog Name:
    Rat/Mouse Insulin ELISA
  • Muscarinic acetylcholine receptor subtypes expressed by mouse bladder afferent neurons. 20394802

    Cell bodies of afferent neurons located in lumbosacral dorsal root ganglia (DRG) provide Adelta- and C-fibres to the urinary bladder, reporting bladder wall tension, volume and noxious stimuli. Recent studies suggested an involvement of muscarinic acetylcholine receptors (mAChRs) not only in detrusor contractility but also in modulating afferent function, and this has been linked to the beneficial effects of muscarinic antagonists in the treatment of overactive bladder. Here, we aimed to determine the inventory of mAChR subtypes expressed by bladder afferent neurons in the mouse. Bladder afferent neurons were identified by retrograde neuronal tracing using Fast Blue (FB) or 1, 1'-dioctadecyl-3, 3, 3', 3'-tetramethylindocarbocyanine perchlorhydrate (DiI) injection into the detrusor muscle. DRG L6-S1 were recognized as the major location of bladder afferent perikarya with an additional smaller peak at L1/L2. Retrogradely labelled bladder afferents located in DRG L4-S2 were subjected to immunohistochemistry or to laser-assisted microdissection with subsequent RT-PCR to study expression of mAChRs subtypes M1R-M5R. Immunolabelling for mAChR subtype M2R, validated on DRG from M2R gene-deficient mice, demonstrated this subtype on 35% of FB-labelled bladder afferents. RT-PCR demonstrated expression of subtypes M2R, M3R and M4R, but not of M1R and M5R, in pooled samples (30 section profiles each) of laser microdissected DiI-labelled bladder afferent cell bodies. In conclusion, bladder afferent neurons express different subtypes of mAChRs (M2R, M3R and M4R). Thus, processing of sensory information from the bladder appears to be under direct cholinergic control.
    Document Type:
    Reference
    Product Catalog Number:
    MAB367
    Product Catalog Name:
    Anti-Muscarinic Acetylcholine Receptor m2 Antibody, clone M2-2-B3
  • α7 nicotinic acetylcholine receptor agonist PNU-282987 attenuates early brain injury in a perforation model of subarachnoid hemorrhage in rats. 21960575

    Early brain injury is an important pathological process after subarachnoid hemorrhage (SAH). The goal of this study was to evaluate whether the α7 nicotinic acetylcholine receptor (α7nAChR) agonist PNU-282987 attenuates early brain injury after SAH and whether α7nAChR stimulation is associated with down-regulation of caspase activity via phosphatidylinositol 3-kinase-Akt signaling.The perforation model of SAH was performed, and neurological score, body weight loss, and brain water content were evaluated 24 and 72 hours after surgery. Western blot and immunohistochemistry were used for quantification and localization of phosphorylated Akt and cleaved caspase 3. Neuronal cell death was quantified with TUNEL staining. α7nAChR antagonist methylcaconitine and phosphatidylinositol 3-kinase inhibitor wortmannin were used to manipulate the proposed pathway, and results were quantified with Western blot.PNU-282987 improved neurological deficits both 24 and 72 hours after surgery and reduced brain water content in left hemispheres 24 hours after surgery. PNU-282987 significantly increased phosphorylated Akt levels and significantly decreased cleaved caspase 3 levels in ipsilateral hemispheres after SAH. Methylcaconitine and wortmannin reversed effects of treatment. Phosphorylated Akt and cleaved caspase 3 were colocalized to neurons in the ipsilateral basal cortex. Phosphorylated Akt was mainly localized in TUNEL-negative cells. PNU-282987 significantly reduced neuronal cell death in the ipsilateral basal cortex.α7nAChR stimulation decreased neuronal cell death and brain edema and improved neurological status in a rat perforation model of SAH. α7nAChR stimulation is associated with increasing phosphorylation of Akt and decreasing cleaved caspase 3 levels in neurons.
    Document Type:
    Reference
    Product Catalog Number:
    MAB377
    Product Catalog Name:
    Anti-NeuN Antibody, clone A60