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Abbondanza, A.

Publications and source records attributed to Abbondanza, A..

2 recordsLinked to original sources

Beta2* Nicotinic Receptors Tune Prefrontal Behavior Through Distinct Neuronal Populations

Beta2 subunit-containing nicotinic acetylcholine receptors (beta2*nAChRs) are highly expressed in the prefrontal cortex (PFC) and critically regulate behavioral and cognitive domains that are disrupted in neuropsychiatric disorders. Despite their therapeutic potential, the cell-type- and circuit-specific functions of beta2* nAChRs remain poorly defined, partially due to the lack of selective pharmacological tools. Here, we delineate the cellular expression patterns and behavioral roles of beta2* nAChRs expressed in a general vs. highly specific neuronal populations of the mouse PFC. Using fluorescence in situ hybridization (FISH), we mapped beta2 nicotinic subunit expression across cortical layers and major neuronal classes. We then employed CRISPR-mediated knockdown (KD) to reduce beta2* nAChRs expression selectively in two distinct PFC neuronal populations and, for comparison, in a striatal population. The KD of beta2* nAChRs in a mixed population of excitatory and inhibitory neurons in deep PFC layers resulted in a mild impairment of social and exploratory behaviors. In contrast, KD in a highly selective population of superficial-layer interneurons expressing the serotonin receptor 5HT3a induced a robust hypersocial phenotype, accompanied by changes in exploratory behavior. Notably, KD of beta2* nAChRs in a rare NPY-expressing striatal population slightly affected similar behavioral domains, but in the opposite direction to PFC manipulations. Together, these findings reveal opposing, cell-type- and region-specific contributions of beta2* nAChRs to behavioral regulations, highlighting the necessity of circuit-resolved targeting strategies to improve the precision and efficacy of therapeutic intervention for neuropsychiatric disorders.

neuroscience↗

Timed sequence task: a new paradigm to study motor learning and flexibility in mice

Motor learning and flexibility allow animals to perform routine actions efficiently while keeping them flexible. There is a number of paradigms used to test cognitive flexibility but not many of them focus specifically on learning of complex motor sequences and their flexibility. While many tests use operant or touchscreen boxes that offer high throughput and reproducibility, the motor actions themselves are mostly simple presses of a designated lever. To focus more on motor actions during the operant task and to probe the flexibility of these well-trained actions, we developed a new operant paradigm for mice, the, "timed sequence task". The task requires mice to learn a sequence of lever presses that have to be emitted in precisely defined time limits. After training, the required pressing sequence and/or timing of individual presses is modified to test the ability of mice to alter their previously trained motor actions. We provide a code for the new protocol that can be used and adapted to common types of operant boxes. In addition, we provide a set of scripts that allow automatic extraction and analysis of numerous parameters recorded during each session. We demonstrate that the analysis of multiple performance parameters is necessary for detailed insight into animals behavior during the task. We validate our paradigm in an experiment using the valproate model of autism as a model of cognitive inflexibility. We show that the valproate mice show superior performance at specific stages of the task, paradoxically due to their propensity to more stereotypic behavior. Significance StatementCognitive flexibility impairment is a crucial component of many neurological disorders and it is frequently evaluated in animal models. As the commonly used tests usually do not focus on motor learning and the ability to adapt motor sequences, we designed a new paradigm to evaluate motor learning and its flexibility. The timed sequence task is automatized and easily accessible as it is based on widely available operant boxes. During the training, the task requires precise timing of each action to force stereotypic performance. Its relative complexity allows detailed analysis of multiple parameters and therefore detailed insight into animals behavior. The task can be used to reveal and understand subtle differences in motor and operant learning and flexibility. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=125 SRC="FIGDIR/small/547172v2_ufig1.gif" ALT="Figure 1"> View larger version (29K): org.highwire.dtl.DTLVardef@ced388org.highwire.dtl.DTLVardef@a19792org.highwire.dtl.DTLVardef@e60f49org.highwire.dtl.DTLVardef@1f5bfa1_HPS_FORMAT_FIGEXP M_FIG C_FIG

animal behavior and cognition↗