Using autoradiographic binding methodology with monoiodinated peptide YY together with the agonists neuropeptide Y (NPY) and NPY (13-36), as well as in situ hybridization with oligonucleotide probes complementary to the NPY Y2 receptor (Y2-R) mRNA, we have studied whether or not intracerebral prion inoculation affects Y2-Rs in male CD-1 mice. Monoiodinated peptide YY binding, mainly representin...

Nitric oxide (NO) production has been widely reported to be required for the induction of long-term potentiation (LTP) in hippocampal CA1 cells. Of the two constitutive isoforms of NO synthase, the endothelial form (eNOS) has been implicated in the induction of LTP in these cells. The distribution of eNOS within CA1 cells is not uniform, however, being present in the cell bodies and apical dend...

In the present study, we used immunohistochemistry and western blot analysis to examine changes in the levels and cellular localization of iron, heavy chain ferritin (ferritin-H), and transferrin in the gerbil hippocampal CA1 region from 30 minutes to 7 days following transient forebrain ischemia. Relative to sham controls, iron reactivity increased significantly in the stratum pyramidale and s...

In the brain, high cognitive functions are encoded by coherent network oscillations. Key players are inhibitory interneurons that, by releasing GABA into principal cells, pace targeted cells. Among these, oriens-lacunosum moleculare (O-LM) interneurons that provide a theta frequency patterned output to distal dendrites of pyramidal cells are endowed with HCN channels responsible for the slowly ...

Group I metabotropic glutamate receptors (mGluRs) are important for hippocampal interneuron function. We used whole-cell recording and confocal imaging to characterize group I mGluR actions in CA1 oriens/alveus interneurons in slices. In tetrodotoxin and ionotropic glutamate receptor antagonists, the group I mGluR specific agonist DHPG increased intradendritic Ca(2+) levels and depolarized inte...

The hippocampal cornu ammonis 2 (CA2) region is unique in being the only CA region receiving inputs from the hypothalamic supramammillary nucleus, of importance in modulating hippocampal theta rhythm, and is seizure resistant in temporal lobe epilepsy. CA2 has, however, been little studied, possibly because of its small size and difficulty encountered in defining its borders. To investigate the...

Hypothyroxinemia affects 35-50% of neonates born prematurely (12% of births) and increases their risk of suffering neurodevelopmental alterations. We have developed an animal model to study the role of maternal thyroid hormones (THs) at the end of gestation on offspring's cerebral maturation. Pregnant rats were surgically thyroidectomized at embryonic day (E) 16 and infused with calcitonin and ...

Current-source density analysis was used to estimate the magnitude of the synaptic excitation at the basal and apical dendritic synapses of CA1 following commissural stimulation in the urethane-anesthetized rat, before and after a theta-frequency patterned primed burst tetanus. Stimulation of the contralateral CA3 or the contralateral CA1 stratum oriens excited both the basal and apical dendrit...