- MeSH
- hospice organizace a řízení MeSH
- lidé MeSH
- péče v hospici psychologie MeSH
- senioři MeSH
- Check Tag
- lidé MeSH
- senioři MeSH
- Publikační typ
- novinové články MeSH
We investigated the functional characteristics of pre- and postsynaptic cholinergic transmission in APPswe/PS1dE9 double transgenic mice at a young age (7-10 weeks) before the onset of amyloid plaque formation and at adult age (5-6 months) at its onset. We compared brain slices from cerebral cortex and hippocampus with amyloid deposits to slices from striatum with no amyloid plaques by 6 months of age. In young transgenic mice we found no impairments of preformed and newly synthesized [(3)H]-ACh release, indicating intact releasing machinery and release turnover, respectively. Adult transgenic mice displayed a significant increase in preformed [(3)H]-ACh release in cortex but a decrease in hippocampus and striatum. The extent of presynaptic muscarinic autoregulation was unchanged. Evoked release of newly synthesized [(3)H]-ACh was significantly reduced in the cortex and hippocampus but unchanged in the striatum. Carbachol-induced G-protein activation in cortical membranes displayed decreased potency but normal efficacy in adult animals and no changes in young animals. These results indicate that functional pre- and postsynaptic cholinergic deficits are not present in APPswe/PS1dE9 transgenic mice before 10 weeks of age, but develop along with beta-amyloid accumulation in the brain.
- MeSH
- acetylcholin nedostatek MeSH
- Alzheimerova nemoc genetika metabolismus patofyziologie MeSH
- amyloid metabolismus MeSH
- amyloidový prekurzorový protein beta genetika MeSH
- cholinergní agonisté farmakologie MeSH
- cholinergní vlákna metabolismus patologie MeSH
- degenerace nervu metabolismus patologie MeSH
- down regulace genetika MeSH
- hipokampus metabolismus patologie patofyziologie MeSH
- modely nemocí na zvířatech MeSH
- mozek - chemie genetika MeSH
- mozek růst a vývoj metabolismus patofyziologie MeSH
- mozková kůra růst a vývoj metabolismus patofyziologie MeSH
- myši transgenní MeSH
- myši MeSH
- orgánové kultury - kultivační techniky MeSH
- presenilin-1 genetika MeSH
- proteiny vázající GTP účinky léků genetika metabolismus MeSH
- receptory muskarinové metabolismus MeSH
- stárnutí metabolismus MeSH
- věkové faktory MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Choline is an essential nutrient necessary for synthesis of membrane phospholipids, cell signalling molecules and acetylcholine. The aim of this study was to detect and characterize the choline transporter-like 1 (CTL1/SLC44A1) protein in CNS tissues and the hybrid neuroblastoma x glioma cell line NG108-15, which synthesizes acetylcholine and has high affinity choline transport but does not express the cholinergic high affinity choline transporter 1. The presence of CTL1 protein in NG108-15 cells was confirmed using our antibody G103 which recognizes the C-terminal domain of human CTL1. Three different cognate small interfering RNAs were used to decrease CTL1 mRNA in NG108-15 cells, causing lowered CTL1 protein expression, choline uptake and cell growth. None of the small interfering RNAs influenced carnitine transport, demonstrating the absence of major non-specific effects. In parental C6 cells knockdown of CTL1 also reduced high affinity choline transport. Our results support the concept that CTL1 protein is necessary for the high affinity choline transport which supplies choline for cell growth. The presence of CTL1 protein in rat and human CNS regions, where it is found in neuronal, glial and endothelial cells, suggests that malfunction of this transporter could have important implications in nervous system development and repair following injury, and in neurodegenerative diseases.
- MeSH
- acetylcholin biosyntéza MeSH
- buněčná diferenciace fyziologie MeSH
- buněčná membrána chemie metabolismus MeSH
- CD antigeny chemie imunologie metabolismus MeSH
- cholin metabolismus MeSH
- down regulace genetika MeSH
- gliom MeSH
- hybridomy MeSH
- imunohistochemie MeSH
- krysa rodu rattus MeSH
- lidé MeSH
- malá interferující RNA fyziologie MeSH
- messenger RNA metabolismus MeSH
- nádorové buněčné linie MeSH
- neuroblastom MeSH
- neurogeneze fyziologie MeSH
- neurony metabolismus MeSH
- proteiny přenášející organické kationty chemie imunologie metabolismus MeSH
- specificita protilátek MeSH
- stimulanty centrálního nervového systému metabolismus MeSH
- terciární struktura proteinů fyziologie MeSH
- zvětšování buněk MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- lidé MeSH
- zvířata MeSH
- Publikační typ
- práce podpořená grantem MeSH
There are five subtypes of muscarinic receptors that serve various important physiological functions in the central nervous system and the periphery. Mental functions like attention, learning, and memory are attributed to the muscarinic M1 subtype. These functions decline during natural aging and an early deficit is typical for Alzheimer s disease. In addition, stimulation of the M1 receptor increases non-amyloidogenic processing of the amyloid precursor protein and thus prevents accumulation of noxious beta-amyloid fragments. The selectivity of classical muscarinic agonists among receptor subtypes is very low due to the highly conserved nature of the orthosteric binding site among receptor subtypes. Herein we summarize some recent studies with the functionally-selective M1 agonist xanomeline that indicate complex pharmacological profile of this drug that includes interactions with and activation of receptor from both orthosteric and ectopic binding sites, and the time-dependent changes of ligand binding and receptor activation. These findings point to potential profitability of exploitation of ectopic ligands in the search for truly selective muscarinic receptor agonists.
- MeSH
- acetylcholin metabolismus MeSH
- agonisté muskarinových receptorů farmakologie MeSH
- guanosintrifosfát metabolismus MeSH
- karbachol farmakologie MeSH
- lidé MeSH
- mozek metabolismus MeSH
- pyridiny farmakologie MeSH
- racionální návrh léčiv * MeSH
- receptor muskarinový M1 agonisté metabolismus MeSH
- thiadiazoly farmakologie MeSH
- vazba proteinů MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
We assessed the integrity of cholinergic neurotransmission in parietal cortex of young adult (7 months) and aged (17 months) transgenic APPswe/PS1dE9 female mice compared to littermate controls. Choline acetyltransferase and acetylcholinesterase activity declined age-dependently in both genotypes, whereas both age- and genotype-dependent decline was found in butyrylcholinesterase activity, vesicular acetylcholine transporter density, muscarinic receptors and carbachol stimulated binding of GTP gamma S in membranes as a functional indicator of muscarinic receptor coupling to G-proteins. Notably, vesicular acetylcholine transporter levels and muscarinic receptor-G-protein coupling were impaired in transgenic mice already at the age of 7 months compared to wild type littermates. Thus, brain amyloid accumulation in this mouse model is accompanied by a serious deterioration of muscarinic transmission already before the mice manifest significant cognitive deficits.
- MeSH
- acetylcholinesterasa metabolismus MeSH
- amyloidový prekurzorový protein beta metabolismus MeSH
- analýza rozptylu MeSH
- financování organizované MeSH
- geneticky modifikovaná zvířata MeSH
- guanosin 5'-O-(3-thiotrifosfát) metabolismus MeSH
- lidé MeSH
- mutace MeSH
- myši MeSH
- N-methylskopolamin MeSH
- nervový přenos genetika MeSH
- piperidiny farmakokinetika metabolismus MeSH
- presenilin-1 genetika MeSH
- receptory muskarinové metabolismus MeSH
- vazba proteinů účinky léků MeSH
- věkové faktory MeSH
- vezikulární transportní proteiny acetylcholinu metabolismus MeSH
- vztah mezi dávkou a účinkem léčiva MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- ženské pohlaví MeSH
- zvířata MeSH
We studied the effects of 3-[3-hexyloxy-1,2,5-thiadiazo-4-yl]-1,2,5,6-tetrahydro-1-methylpyridine (xanomeline) wash-resistant binding on presynaptic muscarinic regulation of electrically evoked [(3)H]acetylcholine (ACh) release from rat brain slices. In both cortical and striatal tissues that possess M(2) and M(4) autoreceptors, respectively, immediate application of 10 microM xanomeline had no effect on evoked [(3)H]ACh release or its inhibition by 10 microM carbachol. In contrast, preincubation with 1, 10, or 100 microM xanomeline for 15 min decreased evoked release of ACh measured after 53 min of washing in xanomeline-free medium in a concentration-dependent manner. The maximal inhibitory effect equaled the immediate effect of the muscarinic full agonist carbachol, and it was completely (at 1 and 10 microM xanomeline) or partially (at 100 microM xanomeline) blocked by 1 microM N-methylscopolamine. Neither presence of N-methylscopolamine during 100 microM xanomeline treatment nor previous irreversible inactivation of the classical receptor binding site using propylbenzylcholine mustard in cortical slices prevented the inhibitory effect of wash-resistantly bound xanomeline. Treatment of cortical slices with xanomeline slightly decreased the number of muscarinic binding sites, and it markedly decreased affinity for N-methylscopolamine. When applied as in acetylcholine release experiments, xanomeline did not impair presynaptic alpha(2)-adrenoceptor-mediated regulation of noradrenaline release. The functional studies in brain tissue reported in this work demonstrate that xanomeline can function as a wash-resistant agonist of native presynaptic muscarinic M(2) and M(4) receptors with both competitive and allosteric components of action.
- MeSH
- acetylcholin sekrece MeSH
- agonisté muskarinových receptorů metabolismus MeSH
- CHO buňky MeSH
- financování organizované MeSH
- křečci praví MeSH
- krysa rodu rattus MeSH
- lidé MeSH
- mozková kůra sekrece účinky léků MeSH
- noradrenalin sekrece MeSH
- potkani Wistar MeSH
- pyridiny farmakologie MeSH
- receptor muskarinový M2 fyziologie účinky léků MeSH
- receptor muskarinový M4 fyziologie účinky léků MeSH
- thiadiazoly farmakologie MeSH
- zvířata MeSH
- Check Tag
- křečci praví MeSH
- krysa rodu rattus MeSH
- lidé MeSH
- mužské pohlaví MeSH
- zvířata MeSH
Several new biocompatible and degradable materials were prepared by chemical modification of sodium hyaluronate. The method of activation of hyaluronate by cyanogen bromide was used and subsequent reaction with nucleophile led to the formation of carbamate. This modification of hydroxyl groups of glycosaminoglycans preserves the carboxyl groups and retains properties of polyelectrolyte. This method affords derivatives easily and the reaction condition correlates with degree of substitution. The experimental results show the effect of reaction conditions (reaction time, ratio of reactants) and effect of substitution on biodegradability. The obtained materials were characterized by nuclear magnetic resonance and Fourier transform infrared spectroscopy. Copyright (c) 2006 Wiley Periodicals, Inc.
- MeSH
- biodegradace MeSH
- biokompatibilní materiály chemická syntéza MeSH
- bromkyan chemie MeSH
- financování organizované MeSH
- gelová chromatografie MeSH
- glykosaminoglykany chemie MeSH
- hyaluronoglukosaminidasa farmakologie MeSH
- hydroxylový radikál chemie MeSH
- karbamáty chemická syntéza MeSH
- kinetika MeSH
- kyselina hyaluronová chemická syntéza chemie MeSH
- nukleární magnetická rezonance biomolekulární MeSH
- rozpustnost MeSH
- skot MeSH
- spektroskopie infračervená s Fourierovou transformací MeSH
- viskozita MeSH
- voda chemie MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- skot MeSH
- zvířata MeSH
