Circadian changes in serum corticosterone levels affect hearing in mice exposed to noise

Abstract

Diffusion properties of the thalamocortical pathways were compared between 30 schizophrenic patients and 22 healthy age-matched and sex-matched volunteers. T1-weighted and diffusion tensor images were used for cortical parcellation and probabilistic tractography to generate population-based thalamocortical pathway maps. The weighted fractional anisotropy and the longitudinal and transversal diffusivity of each pathway were calculated for individual participants. Patients with schizophrenia demonstrated decreased anisotropy and increased longitudinal and transversal diffusivity within the pathways from the mediodorsal nucleus and the pulvinar to the orbitofrontal and parietal-occipital-temporal lobes. Anisotropy decreases and diffusivity increases were correlated with positive and negative syndrome scale scores. Alterations in global diffusion properties within the thalamocortical pathways imply the disruption of brain circuitry in schizophrenic patients.

Psychological Stress on Female Mice Diminishes the Developmental Potential of Oocytes: A Study Using the Predatory Stress Model

“…Both the present results and our previous study [19] indicate that cortisol concentrations in unstressed control mice were relatively lower in blood samples collected early in the morning than in those collected in the afternoon. Serum corticosterone concentrations are also reported to be significantly lower in the morning than in the afternoon in both mice [53] and rats [54]. The present data and our previous study [19] showed that serum cortisol levels were markedly increased in response to both restraint and predatory stress.…”

“…The present data and our previous study [19] showed that serum cortisol levels were markedly increased in response to both restraint and predatory stress. Similarly, significant elevation of corticosterone has been reported in both mice [53] and rats [55], [56] after restraint or noise stress. Furthermore, preliminary observations from our laboratory (unpublished) suggest that serum levels of both cortisol and corticosterone were elevated significantly following restraint stress of mice during the second 24-h after eCG injection and that cortisol (from 13 to 54 ng/ml) was raised to a much greater extent than corticosterone (from 250 to 310 ng/ml).…”

Subcellular plasticity of the corticotropin-releasing factor receptor in dendrites of the mouse bed nucleus of the stria terminalis following chronic opiate exposure

“…These levels in saline and morphine groups are within the basal range of plasma corticosterone levels in mice (Barriga et al, 2001; Kim et al, 2008). …”

“…All blood samples were collected near the start of the light (inactive) phase, corresponding to the trough of the diurnal rhythm in corticosterone secretion (Dallman et al, 1987; Barriga et al, 2001; Kim et al, 2008). Blood was collected from the heart in EDTA-coated microcentrifuge tubes immediately prior to perfusion, and one hour following the last saline or morphine injection.…”

Timing of presentation and nature of stimuli determine retroactive interference with social recognition memory in mice

“…Remarkably, systemic injection of the protein synthesis inhibitor anisomycin blocked juvenile recognition if injections were performed at 3 h, but not if done 6 h after sampling [6,8]. To date we can only speculate about the mechanisms underlying the impact of the tone presentation: One explanation might be that presentation of the loud tone caused stimulus-specific discomfort, stress and/or arousal in the animals [23,24]. Indeed, experimentally increased plasma corticosterone levels during memory consolidation were shown to inhibit long-term memory performance in tasks with low aversive stimulation, but not in tasks based on highly aversive stimuli [25].…”