Life sciences
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Comparative Study
Comparison of the peripheral mediator background of heat injury- and plantar incision-induced drop of the noxious heat threshold in the rat.
Previously we described the drop of the noxious heat threshold in response to mild heat injury or plantar incision. While mild heat injury elicits an immediate and short-lasting thermal hyperalgesia, surgical incision leads to a delayed and sustained heat hyperalgesia. Only very few peripheral mediators of these phenomena have been identified. Therefore the present study aimed at comparing the peripheral mediator background of heat hyperalgesia evoked by mild heat injury or surgical incision. ⋯ Only small differences have been revealed between the examined peripheral mediators of the acute heat hyperalgesia evoked by mild heat injury and the sustained increase in heat responsiveness induced by surgical incision. The B(2) and B(1) bradykinin receptor, P2X purinoceptors, TRPV1 receptor, nitric oxide synthase and lipoxygenase(s) are involved in at least one of these hyperalgesia models.
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The current study was undertaken to determine the role of dorsal hippocampal N-methyl-d-aspartate (NMDA) receptors in nicotine's effect on impairment of memory by ethanol. ⋯ The results suggest the importance of NMDA glutamate system(s) in the CA1 regions of dorsal hippocampus for improving the effect of nicotine on the ethanol-induced amnesia.
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We tested the hypothesis that body fat percentage determines cardiac sympathovagal balance in healthy subjects. ⋯ We conclude that sympathetic activity produced by paced breathing at 0.2Hz can obscure the relationship between body fat percentage and sympathovagal balance and that high body fat percentage may be associated with low sympathetic modulation of the heart rate in healthy adolescent/young adult males.
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Repetitive hypoxic preconditioning (RHP) may provide more efficient protection than single hypoxic preconditioning against renal ischemia/reperfusion-induced injury via hypoxia-induced factor 1alpha (HIF-1alpha)-dependent heat shock protein 70 (HSP70) pathways. ⋯ We demonstrate that RHP promotes HIF-1alpha-dependent HSP70 signaling to reduce renal ischemia/reperfusion injury.
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Long-term glucocorticoid administration is known to induce bone deterioration. Glycogen synthase kinase-3beta (GSK-3beta) signaling reportedly participates in bone remodeling. This study investigated whether GSK-3beta inhibitor could regulate glucocorticoid-induced inhibition of osteoblast differentiation in vitro or bone mass in vivo. ⋯ Inhibition of GSK-3beta abrogated glucocorticoid-induced bone loss by increasing beta-catenin- and Runx2-mediated osteoblast differentiation. Controlling GSK-3beta signaling in bone cells may be a strategy for preventing glucocorticoid-induced osteopenia.