Broad-Spectrum Effects of 4-Aminopyridine to Modulate Amyloid β_1–42-Induced Cell Signaling and Functional Responses in Human Microglia

Microglial VEGF Receptor Response Is an Integral Chemotactic Component in Alzheimer's Disease Pathology

“…All animal procedures were approved by the UBC Animal Care Ethics Committee, with adherence to guidelines of the Canadian Council on Animal Care. Male Sprague Dawley rats weighing 280 -300 g (Charles River Laboratories) were used for stereotaxic injection of A␤ 1-42 , or controls (PBS and reverse peptide A␤ 42-1 ) as previously described (Franciosi et al, 2006;Ryu and McLarnon, 2008). In brief, animals received intraperitoneal injection of an anesthetic mixture (ketamine 100 mg/kg and xylazine 10 mg/kg) and were placed in a stereotaxic apparatus (David Kopf Instruments).…”

“…Brains were then removed, postfixed, cryoprotected, and cut into 40 m sections (Ryu and McLarnon, 2008). Free-floating sections were processed for immunohistochemistry as described previously (Franciosi et al, 2006;Ryu and McLarnon, 2008). Briefly, sections were permeabilized in 0.2% Triton X-100, blocked with 10% NGS, and incubated for 48 h at 4°C with the primary antibodies: anti-Flt-1 (1:200; Santa Cruz Biotechnology), anti-neuronal nuclei (NeuN, a marker for neurons, 1:1000; Millipore Bioscience Research Reagents), and anti-ionized calcium binding adapter molecule 1 (Iba-1, a marker for microglia, 1:500; Wako Chemicals).…”

“…Quantitative image analysis for the immunostained rat hippocampal sections was performed on three equally spaced sections through the level of the injection site (AP: Ϫ3.3 mm). The number of Flt-1 or OX-42/GFAPϩFlt-1(ϩ) cells in the superior blade of the dentate granule cell layer was determined for three sections (Franciosi et al, 2006;Ryu and McLarnon, 2008). The number of Iba-1 or NeuN(ϩ) cells in the CA1 region was quantified at three hippocampal sections.…”

“…Fibrillar A␤ 1-42 and reverse peptide A␤ 1-42 (California Peptides) were first dissolved in 35% acetonitrile (Sigma) and further diluted to 500 M with incremental additions of PBS with vortexing. The peptide solution was subsequently incubated at 37°C for 18 h to promote fibrilization and aggregation and stored at Ϫ20°C (Lue et al, 2001;Franciosi et al, 2006). We also performed immunohistochemical staining (Thioflavin-S staining and A␤ immunostaining) to examine the aggregation state of A␤ peptide in vivo.…”

Status Epilepticus Induces a Particular Microglial Activation State Characterized by Enhanced Purinergic Signaling

“…Therefore, in contrast with some other aspects of microglia activation [for review, see below and Hanisch and Kettenmann (2007)], upregulation of potassium channels does not seem to be differentially regulated according to the context of the activation. It is worth noting, however, that the upregulation of different potassium channels may be a prerequisite for triggering different subsequent aspects of microglia activation (Fordyce et al, 2005;Pannasch et al, 2006;Franciosi et al, 2006;Kaushal et al, 2007).…”