Dysregulation of autophagy may contribute to the progression of various muscle diseases, including Duchenne muscular dystrophy (DMD). Heme oxygenase-1 (HO-1, encoded by ), a heme-degrading enzyme, may alleviate symptoms of DMD, inter alia, through anti-inflammatory properties. In the present study, we determined the role of HO-1 in the regulation of autophagy and mitophagy in animals, a commonly used mouse model of the disease.
View Article and Find Full Text PDFA novel, efficient extraction procedure based on natural deep eutectic solvents (NADES) and ionic liquids (ILs) for determination of 20-hydroxyecdysone (20-E) in spinach has been developed. NADES, the first green extraction agent, with different hydrogen bond donors and acceptors are screened in order to determine extraction efficiencies. NADES consisting of lactic acid and levulinic acid at a molar ratio of 1:1 exhibits the highest yields.
View Article and Find Full Text PDFBackground: In regards to peri-anesthetic morbidity considerations, morbidly obese patients often have full stomach for extended periods secondary to delayed gastric emptying. Additionally, they may have difficulty lying supine because of multiple reasons.
Study Objectives: The purpose of the study was to compare endotracheal intubation of morbidly obese patients placed in semi-erect position with the rapid sequence induction in the supine position using GlideScope video laryngoscopy.
Background: The resident selection process could be improved if United States Medical Licensing Examination (USMLE) scores obtained during residency application were found to predict success on the American Board of Anesthesiology (ABA) written examination (part 1). In this study, we compared USMLE performance during medical school to anesthesiology residency standardized examination performance.
Methods: Sixty-nine anesthesiology residents' USMLE, ABA/American Society of Anesthesiologists (ASA) In-Training Examination, and ABA written board examination (part 1) scores were compared.
Whole-cell patch-clamp recordings were obtained from nodose ganglion neurons acutely dissociated from 10-30-day-old rats to characterize the Ca2+ channel types that are modulated by GABA(B) and mu-opioid receptors. Five components of high-threshold current were distinguished on the basis of their sensitivity to blockade by omega-conotoxin GVIA, nifedipine, omega-agatoxin IVA and omega-conotoxin MVIIC. Administration of the mu-opioid agonist H-Tyr-D-Ala-Gly-Phe(N-Me)-Gly-ol (0.
View Article and Find Full Text PDFWhole-cell patch-clamp recordings were performed together with time-resolved measurements of membrane capacitance (Cm) in nerve terminals acutely dissociated from neurohypophysis of adult rats to investigate modulation of Ca2+ currents and secretion by activation of opioid receptors. Bath superfusion of the kappa-opioid agonists U69,593 (0.3-1 microM), dynorphin A (1 microM), or U50,488H (1-3 microM) reversibly suppressed the peak amplitude of Ca2+ currents 32.
View Article and Find Full Text PDFWhole-cell patch-clamp recordings were used to characterize calcium channel types that are modulated by mu-opioid receptor activation in rat dorsal root ganglion (DRG) neurons. Five distinct components of high-threshold calcium current were isolated on the basis of their sensitivity to the selective channel blockers omega-conotoxin GVIA, nifedipine, omega-conotoxin MVIIC, or omega-agatoxin IVA. The mu-opioid selective agonist Tyr-Pro-NMePhe-D-Pro-NH2 (PLO17) routinely suppressed high-threshold currents and this effect was always reduced by omega-conotoxin GVIA.
View Article and Find Full Text PDFWhole-cell patch-clamp recordings were used to examine the regulation of voltage-dependent calcium channels by mu- and kappa-opioid receptors in acutely isolated rat dorsal root ganglion (DRG) sensory neurons. Agonists selective for either mu- (Tyr-Pro-NMePhe-D-Pro-NH2, PLO17) or kappa-opioid receptors (dynorphin A, U69,593) inhibited high-threshold calcium currents in a reversible and naloxone-sensitive manner, whereas administration of D-Pen2,5-enkephalin, a delta-selective agonist, was without effect. However, none of the opioids reduced low-threshold T-type currents.
View Article and Find Full Text PDFIt has recently been shown that the activation of mu-opioid receptors inhibits several components of calcium channel current in rat DRG sensory neurons. mu-Opioid receptors, acting through the pertussis toxin (PTX)-sensitive substrate Gi, also reduce the activity of neuronal adenylate cyclase, but the relationship of this effect to changes in calcium channel activity has yet to be determined. Using whole-cell recordings from acutely isolated rat DRG neurons, we examined the ability of the mu-opioid-selective agonist Tyr-Pro-NMe-Phe-D-Pro-NH2 (PLO17) to reduce calcium current after treatment with PTX and in the presence of the nonhydrolyzable GTP analog guanosine 5'-[-thio]triphosphate (GTP gamma S), to assess the role of G-proteins in the coupling of mu-opioid receptors to calcium channels.
View Article and Find Full Text PDFGlutamate-gated ion channels mediate excitatory synaptic transmission in the central nervous system and are involved in synaptic plasticity, neuronal development and excitotoxicity (5,24). These ionotropic glutamate receptors were classified according to their preferred agonists as AMPA (alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid), KA (kainate), and NMDA (N-methyl-D-aspartate) receptors [Trends Pharmacol. Sci.
View Article and Find Full Text PDFSubstance P and neurokinin A both potentiated N-methyl-D-aspartate (NMDA)-induced currents recorded in acutely isolated neurons from the dorsal horn of the rat. To elucidate the mechanism underlying this phenomenon, we measured the effects of tachykinins and glutamate receptor agonists on [Ca2+]i in these cells. Substance P, but not neurokinin A, increased [Ca2+]i in a subpopulation of neurons.
View Article and Find Full Text PDFWhole-cell patch-clamp technique of freshly isolated rat spinal dorsal horn (DH) neurons, intracellular recording from DH neurons in a slice preparation, and high performance liquid chromatography with fluorimetric detection of release of endogenous glutamate and aspartate from spinal cord slice following activation of primary afferent fibers were employed to investigate interactions between excitatory amino acids (EAA) and tachykinins [substance P (SP) and neurokinin A (NKA)]. Potentiation of N-methyl-D-aspartate (NMDA)-, quisqualate (QA)- and alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA)-, but not kainate-induced currents by SP and NKA was found. Spantide II, a claimed novel nonselective tachykinin antagonist, effectively blocked the SP (2 nM)-induced potentiation of the responses of DH neurons to NMDA.
View Article and Find Full Text PDFThe effects of the metabotropic glutamate receptor agonist (1S,3R)-1-aminocyclopentane-1,3-dicarboxylic acid [(1S,3R)-ACPD] were examined on responses mediated by the ionotropic glutamate receptor agonists N-methyl D-aspartate (NMDA), alpha-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid (AMPA), and kainic acid (KA), in neurons acutely isolated from the dorsal horn of the rat spinal cord. (1S,3R)-ACPD produced an increase in the intracellular Ca2+ concentration in 50% of acutely isolated dorsal horn neurons, which could be prevented by blockers of voltage-sensitive Ca2+ channels. (1S,3R)-ACPD markedly potentiated increases in the intracellular Ca2+ concentration induced by NMDA, AMPA, and KA but not by 10-50 mM KCl.
View Article and Find Full Text PDF1. In freshly isolated spinal dorsal horn (DH) neurons (laminae I-III) of the young rat, the effects of tachykinins (substance P, neurokinin A) on inward current induced by excitatory amino acids were studied under whole-cell voltage-clamp conditions. 2.
View Article and Find Full Text PDFBiosens Bioelectron
August 1992
The effect of cross-linker chain length on the activities of choline oxidase (ChO) and glucose oxidase (GOx) immobilized on oxidized silicon wafers has been investigated for the cross-linkers N-succinimidyl 4-maleimido-butyrate (GMBS) and N-succinimidyl 6-maleimidocaproate (EMCS). Enzyme activities were determined with an indirect fluorometric assay based on the production of hydrogen peroxide. Immobilization of ChO or GOx onto oxidized silicon with either cross-linker resulted in an 86-99% loss in enzymatic activity relative to the soluble form of the flavoprotein.
View Article and Find Full Text PDFPheochromocytoma PC12 cells incubated with and without nerve growth factor were investigated using the patch-clamp technique in the whole-cell recording mode, and the concentration clamp method in the rat. On the fourth day of incubation with nerve growth factor, sodium potential-activated ionic currents appeared in the membranes of the most morphologically differentiated cells. At the same period a three-fold increase of acetylcholine-activated current density, compared with the cells incubated without nerve growth factor, was observed.
View Article and Find Full Text PDFThe action of glycine and GABA on isolated lamprey spinal cord neurons was investigated by means of intracellular perfusion and concentration clamp techniques. These amino acids activated desensitizing chloride ionic conductances. The concentrations of agonists evoking half-maximum effects (ED50) were equal to 16 microM and 1.
View Article and Find Full Text PDFThe whole-cell patch-clamp technique was used to examine effects of mu-opioid receptor agonist Tyr-D-Ala-Gly-Me-Phe-Gly-ol-enkephalin (DAGO) on N-methyl-D-aspartate (NMDA)-induced currents in freshly enzymatically and/or mechanically dissociated rat spinal dorsal horn neurons (laminae I-III). Here we report that the responses of dorsal horn neurons to NMDA were modulated by DAGO in a complex manner. When applied simultaneously with, or prior to NMDA, DAGO (10-100 nM) initially suppressed the response to NMDA in 52% of examined cells.
View Article and Find Full Text PDF1. The membrane currents elicited by L-glutamate and glycine applications in morphologically different neurone types were investigated in isolated spinal cord cells from the lumbar enlargement of 6 to 11-day-old chick embryos. The whole-cell patch-clamp technique and concentration clamp methods have been used.
View Article and Find Full Text PDFEffect of noradrenaline precursors (L-alanine, L-phenylalanine, L-tyrosine, L-DOPA and dopamine) on glycine and NMDA receptors of freshly isolated spinal neurones of chick embryo were investigated by means of the whole cell patch-clamp and concentration clamp techniques. L-alanine and L-DOPA were found to be glycine agonists which can potentiate NMDA responses. L-tyrosine does not activate glycine receptor but potentiate NMDA one.
View Article and Find Full Text PDFEffects of inhibitory mediators on the membranes of isolated lamprey spinal cord neurones were investigated by means of whole-cell recording and concentration clamp techniques. Glycine and gamma-aminobutyric acid (GABA) applications evoked desensitizing chloride currents. The concentrations at half-maximum effects were 16 microM for glycine- and 1.
View Article and Find Full Text PDFResponses of isolated spinal cord neurons of lamprey on glycine and gamma-aminobutyric acid (GABA) were investigated by means of intracellular perfusion and concentration clamp techniques. Responses on both amino acids exhibited fast but not full desensitization. Preincubation of neurons in the solution of one mediator led to full disappearance of the response to other mediator.
View Article and Find Full Text PDFIonic currents induced by application of L-3, 4-dihydroxyphenylalanine (L-DOPA) and acidic amino acids: L-glutamate, kainate, N-methyl-D-aspartate (NMDA) were investigated in experiments on isolated spinal cord neurons of the lamprey by means of whole-cell recording and concentration clamp methods. L-DOPA was found to activate glycine, but not excitatory amino acid receptors.
View Article and Find Full Text PDFNeirofiziologiia
September 1987
Isolated spinal cord neurons of 6-11 day old chick embryos were investigated under conditions of intracellular perfusion and voltage clamp. Glycine-activated chloride conductivity characteristics of neuronal membranes did not change at the investigated stages. Concentrations evoking half-effect (7.
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