Local microinjection of CoCl2 (1 mm in 100 nL) into the MeA significantly reduced the pressor and bradycardic responses caused by NA microinjection (21 nmol in 200 nL) into the LSA. In contrast, microinjection of CoCl2 into the BNST or DBB did not change the cardiovascular responses to NA into the LSA. The results indicate that synapses within the MeA, but not in BNST or DBB, are involved in the cardiovascular pathway activated by NA microinjection into the
LSA. “
“The presubiculum, at the transition from the hippocampus to the cortex, is a key area for spatial information coding but the anatomical and physiological basis of presubicular function remains unclear. Here we correlated the structural and physiological properties of single neurons of the presubiculum Stem Cell Compound Library concentration in vitro. Unsupervised cluster analysis based on dendritic length and form, soma location, firing pattern and action potential properties Z-VAD-FMK in vivo allowed us to classify principal neurons into three major cell types. Cluster 1 consisted of a population of small regular spiking principal cells in layers II/III. Cluster 2 contained intrinsically burst firing pyramidal cells of layer IV, with a resting potential close to threshold.
Cluster 3 included regular spiking cells of layers V and VI, and could be divided into subgroups 3.1 and 3.2. Cells of cluster 3.1 included pyramidal, multiform and inverted pyramidal cells. Cells of cluster 3.2 Acyl CoA dehydrogenase contained high-resistance pyramidal neurons that fired readily in response to somatic current injection. These data show that presubicular principal
cells generally conform to neurons of the periarchicortex. However, the presence of intrinsic bursting cells in layer IV distinguishes the presubicular cortex from the neighbouring entorhinal cortex. The firing frequency adaptation was very low for principal cells of clusters 1 and 3, a property that should assist the generation of maintained head direction signals in vivo. “
“Axonal injury is an important contributor to the behavioral deficits observed following traumatic brain injury (TBI). Additionally, loss of myelin and/or oligodendrocytes can negatively influence signal transduction and axon integrity. Apoptotic oligodendrocytes, changes in the oligodendrocyte progenitor cell (OPC) population and loss of myelin were evaluated at 2, 7 and 21 days following TBI. We used the central fluid percussion injury model (n = 18 and three controls) and the lateral fluid percussion injury model (n = 15 and three controls). The external capsule, fimbriae and corpus callosum were analysed. With Luxol Fast Blue and RIP staining, myelin loss was observed in both models, in all evaluated regions and at all post-injury time points, as compared with sham-injured controls (P ≤ 0.05). Accumulation of β-amyloid precursor protein was observed in white matter tracts in both models in areas with preserved and reduced myelin staining.