https://ogma.newcastle.edu.au/vital/access/ /manager/Index ${session.getAttribute("locale")} 5 Heterogeneous responses to antioxidants in noradrenergic neurons of the locus coeruleus indicate differing susceptibility to free radical content https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:17232 2+_ concentration but may influence mitochondrial function as both antioxidant treatments modulated mitochondrial membrane potential. These suggest that the antioxidant-sensitive subpopulations of LC neurons may be more susceptible to oxidative stress (e.g., due to ATP depletion and/or overactivation of Ca2+_ dependent pathways). Indeed it may be that this subpopulation of LC neurons is preferentially destroyed in neurological pathologies such as Parkinson’s disease. If this is the case, there may be a protective role for antioxidant therapies.]]> Wed 11 Apr 2018 14:36:25 AEST ]]> Phasic contractions of the mouse vagina and cervix at different phases of the estrus cycle and during late pregnancy https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:16822 2+ release from sarcoplasmic/endoplasmic reticulum Ca2+-ATPase (SERCA) -dependent intracellular Ca2+ stores; and 3) c-Kit and/or vimentin immunoreactive ICs have a role in pacemaking. Methodology/Principal Findings: Vaginal and cervical contractions were measured in vitro, as was the distribution of c-Kit and vimentin positive interstitial cells (ICs). Cervical smooth muscle was spontaneously active in estrus and metestrus but quiescent during proestrus and diestrus. Vaginal smooth muscle was normally quiescent but exhibited phasic contractions in the presence of oxytocin or the K+ channel blocker tetraethylammonium (TEA) chloride. Spontaneous contractions in the cervix and TEA-induced phasic contractions in the vagina persisted in the presence of cyclopiazonic acid (CPA), a blocker of the SERCA that refills intracellular SR Ca2+ stores, but were inhibited in low Ca2+ solution or in the presence of nifedipine, an inhibitor of L-type Ca2+channels. ICs were found in small numbers in the mouse cervix but not in the vagina. Conclusions/Significance: Cervical smooth muscle strips taken from mice in estrus, metestrus or late pregnancy were generally spontaneously active. Vaginal smooth muscle strips were normally quiescent but could be induced to exhibit phasic contractions independent on phase of the estrus cycle or late pregnancy. Spontaneous cervical or TEA-induced vaginal phasic contractions were not mediated by ICs or intracellular Ca2+ stores. Given that vaginal smooth muscle is normally quiescent then it is likely that increases in hormones such as oxytocin, as might occur through sexual stimulation, enhance the effectiveness of such pacemaking until phasic contractile activity emerges.]]> Wed 11 Apr 2018 13:40:08 AEST ]]> Crosstalk between mitochondria, calcium channels and actin cytoskeleton modulates noradrenergic activity of locus coeruleus neurons https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:36209 c but does not exclude action at intracellular microdomains. Further to this, the incubation of slices with cytochalasin D, an agent that depolymerises the actin cytoskeleton, inhibited the hyperpolarizing response indicating an involvement of the actin cytoskeleton. The data are consistent with the hypothesis that there is a crosstalk between mitochondria and L-type Ca²⁺ channels leading to modulation of noradrenergic neuronal activity mediated by the actin cytoskeleton.]]> Tue 03 Mar 2020 15:35:08 AEDT ]]> Ketamine anesthesia helps preserve neuronal viability https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:9604 Sat 24 Mar 2018 08:39:39 AEDT ]]>