Sandra Peña de Ortíz

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The cAMP-responsive element binding protein (CREB) family of transcription factors is thought to be critical in memory formation. To define the role of CREB in distinct memory processes, we derived transgenic mice with an inducible and reversible CREB repressor by fusing CREBS133A to a tamoxifen (TAM)-dependent mutant of an estrogen receptor ligand-binding(More)
Extinction of conditioned fear is thought to form a long-term memory of safety, but the neural mechanisms are poorly understood. Consolidation of extinction learning in other paradigms requires protein synthesis, but the involvement of protein synthesis in extinction of conditioned fear remains unclear. Here, we show that rats infused intraventricularly(More)
Nurr1 expression is up-regulated in the brain following associative learning experiences, but its relevance to cognitive processes remains unclear. In these studies, rats initially received bilateral hippocampal infusions of control or antisense oligodeoxynucleotides (ODNs) 1 h prior to training in a holeboard spatial discrimination task. Such pre-training(More)
The durability of declarative memory suggests that it has either a chemical or a structural basis. Current models of long-term memory are based on the general assumption that traces of memory are stored by structural modifications of synaptic connections, resulting in alterations in the patterns of neural activity. Changes in gene expression, regulated at(More)
Protein kinases are considered essential for the processing and storage of information in the brain. However, the dynamics of protein kinase activation in the hippocampus during spatial learning are poorly understood. In this study, rats were trained to learn a holeboard spatial discrinmination task and the activity profiles for cyclic adenosine(More)
We studied the regulation of the expression of the inducible orphan nuclear receptor known as HZF-3 (or Nurr1) in acquisition of conditioned taste aversion in rats. Our results show that HZF-3 expression in the lateral/basolateral (LA/BLA) amygdala complex was significantly up-regulated when both the conditioned and the unconditioned stimuli were paired,(More)
Learning and long-term memory are thought to involve temporally defined changes in gene expression that lead to the strengthening of synaptic connections in selected brain regions. We used cDNA microarrays to study hippocampal gene expression in animals trained in a spatial discrimination-learning paradigm. Our analysis identified 19 genes that showed(More)
The long-term storage of information in the brain known as long-term memory (LTM) depends on a variety of intracellular signaling cascades utilizing calcium (Ca2+) and cyclic adenosine monophosphate as second messengers. In particular, Ca(+2)/phospholipid-dependent protein kinase C (PKC) activity has been proposed to be necessary for the transition from(More)
Lithium (Li+) is a drug used for the treatment of neuropsychiatric disorders, whereas Nuclear receptor-related factor 1 (Nurr1) has been implicated in normal and aberrant cognitive processes. Li+'s effects on cognition and Nurr1 expression were examined. Rats were exposed to Li+ in their diet for 4 weeks and only those reaching Li+ blood concentrations(More)
The immediate-early gene hzf-3, also known as nurr1, is a member of the inducible orphan nuclear receptor family and is one candidate in the search for genes associated with learning and memory processes. Here we report that acquisition of a spatial food search task is accompanied by elevated levels of hzf-3 mRNA in the hippocampus. Adult male Long-Evans(More)