Objectives: This article presents an low-cost experimental setup for visualizing refraction anomalies caused by high-intensity focused ultrasound (HIFU). The technique is based on Schlieren imaging, commonly used to visualize temperature and pressure differences in a medium. With this setup, double images of the Schlieren or their shadows to be investigated occur, so that the experimental setup is modified to avoid these double image artifacts.
View Article and Find Full Text PDFAs an endogenous agonist at the cannabinoid receptor CB1 and the capsaicin-receptor TRPV1, anandamide may exert both anti- and pronociceptive actions. Therefore we studied the effects of anandamide and other activators of both receptors on changes in free cytosolic calcium ([Ca(2+)](i)) in acutely dissociated small dorsal root ganglion neurons (diameter: < or =30 microm). Anandamide (10 microM) increased [Ca(2+)](i) in 76% of the neurons.
View Article and Find Full Text PDFhCAT-3 (human cationic amino acid transporter type three) was investigated with both the two-electrode voltage clamp method and tracer experiments. Oocytes expressing hCAT-3 displayed less negative membrane potentials and larger voltage-dependent currents than native or water-injected oocytes did. Ion substitution experiments in hCAT-3-expressing oocytes revealed a large conductance for Na+ and K+.
View Article and Find Full Text PDFTransient receptor potential-vanilloid type-1 (TRPV1) is a ligand-gated cation channel with preference for divalent cations, especially Ca(2+) (sequence of conductances: Ca(2+)>Mg(2+)>Na(+) approximately/= K(+) approximately/= Cs(+)). In the present study, the two-electrode voltage-clamp technique was used on oocytes of Xenopus laevis expressing TRPV1 to evaluate whether human TRPV1 also conducts protons. In medium devoid of K(+), Na(+), Mg(2+), and Ca(2+), capsaicin 1 microM induced a significant inward current (62% of the current in physiological medium).
View Article and Find Full Text PDFThe neuropeptide nociceptin/orphanin FQ (N/OFQ), the endogenous ligand of the opioid receptor-like 1 (ORL1) receptor, has been shown to play a prominent role in the regulation of several biological functions such as pain and stress. Here we describe the isolation and characterization of N/OFQ binding biostable RNA aptamers (Spiegelmers) using a mirror-image in vitro selection approach. Spiegelmers are L-enantiomeric oligonucleotide ligands that display high affinity and specificity to their targets and high resistance to enzymatic degradation compared to D-oligonucleotides.
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