In contrast, MHV-2, a nondemyelinating MHV strain, does not induce ON. Results reveal a reproducible virus-induced ON model important for the evaluation of novel therapies.”
“SR58611A is a selective beta(3)-adrenoceptor (Adrb3) agonist which GW4064 chemical structure has demonstrated antidepressant and anxiolytic properties in rodents. The present study confirmed the detection of Adrb3 mRNA transcript in rodent brain sub-regions and evaluated the effect of SR58611A on serotonergic and noradrenergic transmission in rats and mice in an attempt to elucidate the mechanism(s) underlying these properties.
SR58611A (3 and 10 mg/kg, p.o.) increased the synthesis of 5-HT and
tryptophan (Trp) levels in several rodent brain areas (cortex, hippocampus, Selleckchem LEE011 hypothalamus, striatum). Moreover, SRS8611A (10 mg/kg, p.o.) increased the release of 5-HT assessed by in vivo microdialysis in rat prefrontal cortex. Systemic (3 mg/kg, i.v.) or chronic administration of SR58611A (10 mg/kg, p.o.), in contrast to fluoxetine (15 mg/kg, p.o.), did not modify the activity of serotonergic neurons in the rat dorsal raphe
nucleus. The increase in 5-HT synthesis induced by SR58611A was not observed in Adrb3s knockout mice, suggesting a selective involvement of Adrb3s in this effect.
SR58611A (3 and 10 mg/kg, p.o.) did not modify norepinephrine synthesis and metabolism but increased its release in rat brain. Repeated administration of SR58611A (10 mg/kg, p.o.) did not modify basal norepinephrine release in rat prefrontal cortex whereas it prevented its tail-pinch stress-induced
enhancement similarly to reboxetine (15 mg/kg, p.o.). Finally SR58611A increased the firing rate of noradrenergic neurons in the rat locus coeruleus following systemic (3 mg/kg, i.v.) during or local (0.01 and 1 mu M) but not chronic (10 mg/kg, p.o.) administration.
These results suggest that the anxiolytic- and antidepressant-like activities of SR58611A involve an increase of brain serotonergic and noradrenergic neurotransmissions, triggered by activation of Adrb3s. (C) 2008 IBRC. Published by Elsevier Ltd. All rights reserved.”
“Unlike other class I viral fusion proteins, spike proteins on severe acute respiratory sydrome coronavirus virions are uncleaved. As we and others have demonstrated, infection by this virus depends on cathepsin proteases present in endosomal compartments of the target cell, suggesting that the spike protein acquires its fusion competence by cleavage during cell entry rather than during virion biogenesis. Here we demonstrate that cathepsin L indeed activates the membrane fusion function of the spike protein. Moreover, cleavage was mapped to the same region where, in coronaviruses carrying furin-activated spikes, the receptor binding subunit of the protein is separated from the membrane-anchored fusion subunit.