Neuroscience
-
Wobbler mice are experimental models for amyotrophic lateral sclerosis. As such they show motoneuron degeneration, motor deficits, and astrogliosis and microgliosis of the spinal cord. Additionally, Wobbler mice show increased plasma, spinal cord and brain corticosterone levels and focal adrenocortical hyperplasia, suggesting a pathogenic role for glucocorticoids in this disorder. ⋯ Treatment of Wobbler mice with CORT 113176 reversed the abnormalities of motoneurons and down-regulated proinflammatory mediators and glial reactivity. Expression of glutamate transporters GLT1 and GLAST mRNAs and GLT1 protein was significantly enhanced over untreated Wobblers. In summary, antagonism of GR with CORT 113176 prevented neuropathology and showed anti-inflammatory and anti-glutamatergic effects in the spinal cord of Wobbler mice.
-
Experience-dependent synaptic plasticity is an important component of both learning and motivational disturbances found in addicted individuals. Here, we investigated the role of cocaine experience-dependent plasticity at excitatory synapses in the nucleus accumbens shell (NAcSh) in relapse-related behavior in mice with a history of volitional cocaine self-administration. ⋯ Furthermore, we show that these effects are due to α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR)-specific mechanisms that differ depending on the nature and context of the reinstatement-inducing stimuli. Together, our findings identify common themes as well as differential mechanisms that are likely important for the ability of diverse environmental stimuli to drive relapse to addictive-like cocaine-seeking behavior.
-
Selective afferent activation can be used to improve somatosensory function, possibly by altering cortical inhibitory circuit activity. Peripheral electrical stimulation (PES) is widely used to induce selective afferent activation, and its effect may depend on PES intensity. Therefore, we investigated the effects of high- and low-intensity PES applied to the right index finger on tactile discrimination performance and cortical somatosensory-evoked potential paired-pulse depression (SEP-PPD) in 25 neurologically healthy subjects. ⋯ High-intensity PES decreased N20_SEP-PPD in the GOT improvement group but increased N20_SEP-PPD in the GOT decrement group. Furthermore, a greater decrease in GOT discrimination threshold was significantly associated with a greater N20_SEP-PPD decrease in the GOT improvement group. These results suggest that high-intensity PES can improve somatosensory perception in subjects with low baseline function by modulating cortical inhibitory circuits in primary somatosensory cortex.
-
Life satisfaction reflects an individual's general evaluation of their overall quality of life. It has been hypothesized that relationship status (i.e. state of intimate relationship such as marriage, unmarried cohabiting, dating with others, single or divorce) may influence individual life satisfaction. However, there is little accessible empirical evidence that allows us to explore this proposition. ⋯ These effects were independent of emotional, instrumental support, and socioeconomic status. Besides, statistical significance of the moderation effect pertaining to relationship status was lost once perceived stress was included as a covariate into the moderation model. Our findings provided empirical evidence for the potentially positive role of relationship status in life satisfaction, and also showed that remission of stress may be a critical factor.
-
Maternal deprivation (MD) in rhesus monkeys has been demonstrated to be an effective model to mimic early adversity in humans because of the close phylogenetic similarity affinity. Although behavioral and hormonal abnormalities have been observed in MD monkeys, the neurobiological underpinning of the long-term deleterious effect of MD on monkeys is still unclear. In this study, we assessed emotional changes and socio-behavioral abnormalities induced by long-term MD and assessed structural alterations of gray matter volume (GMV) and white matter integrity (WMI) in 15 MD rhesus monkeys and in 15 age-, gender-matched normal controls (NC) using voxel-based morphology and voxel-based analysis methods. ⋯ Moreover, the mean FA values in pSTS showed positive correlation with the stereotypical behavioral durations in MD monkeys and negative correlation with social grooming durations in NC monkeys. Our findings indicated that the deleterious effects of MD on rhesus monkeys resulted in structural abnormalities in the visual cortex and premature myelination in the pSTS. These findings provide new insights into understanding the impact of maternal deprivation on the neurological basis of brain development.