Neuroscience
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Individuals have different levels of stress sensitivity. An individual's predisposition to experience negative life events (NLEs) may make him/her more vulnerable to a series of psychopathological and physical diseases. However, the neuroanatomical correlates of individual differences in sensitivity to NLEs remain unknown. ⋯ This region was thought to play an important role in introception. Importantly, our study revealed that rumination served as a mediator between the rGMV of the VLPFC and individual NLEs sensitivity. These findings suggest that people with greater VLPFC might be more inclined to ruminate and the ruminative response style might make them more sensitive to NLEs.
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Cervical proprioception plays a key role in postural control, but its specific contribution is controversial. Postural impairment was shown in whiplash injuries without demonstrating the sole involvement of the cervical spine. The consequences of degenerative cervical spine diseases are underreported in posture-related scientific literature in spite of their high prevalence. ⋯ Prior to surgery, in the eyes closed condition, the herniated disc group was more stable than the spondylosis group. After surgery, the contribution of visual input to postural control in a dynamic visual environment was reduced in both cervical spine diseases whereas in a stable visual environment visual contribution was reduced only in the spondylosis group. The relative importance of visual and proprioceptive inputs to postural control varies according to the type of pathology and surgery tends to reduce visual contribution mostly in the spondylosis group.
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In the present study, we addressed the question of whether the distinct patterns of heat shock protein (HSP) 70 and HSP90 expressions in the brain region represents the regional specific responses to status epilepsticus (SE) in an effort to better understand the role of HSPs in epileptogenic insult. HSP70 immunoreactivity was increased in CA3 pyramidal cells as well as dentate granule cells at 12h-1week after SE. HSP70 immunoreactivity was transiently increased in neurons within the piriform cortex (PC) following SE. ⋯ In contrast to HSP70, HSP90 immunoreactivity was decreased in CA1-3 pyramidal cells at 4days-4weeks after SE. In addition, HSP90 immunoreactivity was decreased in PC neurons at 12h-4weeks after SE. linear regression analysis showed a direct proportional relationship between the intensity of NeuN and that of HSP90. Therefore, these findings suggest that HSP90 degradation may be closely related to neuronal vulnerability to SE insult.
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The expression of brain-derived neurotrophic factor (BDNF), which is found in the pro-BDNF, truncated-BDNF and mature-BDNF isoforms, changes with learning. Mature-BDNF shows a peak of late expression in the hippocampus that is involved in the persistence of aversive memory in rodents. However, the role of BDNF in the hippocampal synaptic mechanisms involved in the classical conditioning aversive memory in birds still needs clarification. ⋯ The data indicate that the tone-shock conditioning induced the activation of molecular pathways of BDNF in the hippocampus and amygdala of the pigeons. The decreases in the content of truncated- and pro-BDNF isoforms found in conditioned pigeons may suggest cleavage mechanisms induced by the training. Our data confirm previous observations of rodent studies and extend these observations to pigeons, revealing that, in spite of the anatomical differences between the hippocampus of rodents and pigeons, there are functional and molecular mechanisms that are conservative between the species.
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Not only is the inferior colliculus (IC) a highly important center of integration within the central auditory pathway, but it may also play a modulatory role in sensory-motor circuitry. Previous evidence from our laboratory relating the IC to motor behavior shows that glutamate-mediated mechanisms within the IC modulate haloperidol-induced catalepsy. The high density of GABAergic receptors in the IC led to this study of a possible link between these receptors, haloperidol-induced catalepsy, and a possible involvement of the blockade of dopaminergic receptors. ⋯ However, the microinjection of haloperidol (2.5 or 5.0μg/0.5μl) bilaterally into the IC did not induce catalepsy. Therefore, our results suggest the involvement of the IC in the modulation of catalepsy induced by haloperidol, even though the dopaminergic mechanisms of the IC are unable to induce catalepsy when blocked by the direct microinjection of haloperidol. It is thus possible that the IC plays a role in sensorimotor gating and that GABA-mediated mechanisms are involved.