0000000000279508
AUTHOR
Eero Castrén
Effects of the Antidepressant Fluoxetine on the Somatostatin Interneurons in the Basolateral Amygdala
Although the precise mechanism of action of antidepressant drugs remains elusive, the neuroplastic hypothesis has gained acceptance during the last two decades. Several studies have shown that treatment with antidepressants such as Fluoxetine is associated with enhanced plasticity in control animals, especially in regions such as the visual cortex, the hippocampus and the medial prefrontal cortex. More recently, the basolateral amygdala has been shown to be affected by Fluoxetine leading to a reopening of critical period-like plasticity in the fear and aggression circuits. One of the key elements triggering this type of brain plasticity are inhibitory networks, especially parvalbumin intern…
Chronic fluoxetine treatment alters the structure, connectivity and plasticity of cortical interneurons
Novel hypotheses suggest that antidepressants, such as the selective serotonin reuptake inhibitor fluoxetine, induce neuronal structural plasticity, resembling that of the juvenile brain, although the underlying mechanisms of this reopening of the critical periods still remain unclear. However, recent studies suggest that inhibitory networks play an important role in this structural plasticity induced by fluoxetine. For this reason we have analysed the effects of a chronic fluoxetine treatment in the hippocampus and medial prefrontal cortex (mPFC) of transgenic mice displaying eGFP labelled interneurons. We have found an increase in the expression of molecules related to critical period pla…
Psychedelics promote plasticity by directly binding to BDNF receptor TrkB
10 paginas, 15 fguras
Pharmacological Manipulation of Critical Period Plasticity
Neuronal networks are refined through an activity-dependent competition during critical periods of early postnatal development. Recent studies have shown that critical period plasticity is influenced by a number of environmental factors, including drugs that are widely used for the treatment of brain disorders. These findings suggest a new paradigm, where pharmacological treatments can be used to open critical period–like plasticity in the adult brain. The plastic networks can then be modified through rehabilitation or psychotherapy to rewire those abnormally wired during development. This kind of combination of pharmacotherapy with physical or psychological rehabilitation may open a new op…
The Aromatase Gene CYP19A1: Several Genetic and Functional Lines of Evidence Supporting a Role in Reading, Speech and Language
Inspired by the localization, on 15q21.2 of the CYP19A1 gene in the linkage region of speech and language disorders, and a rare translocation in a dyslexic individual that was brought to our attention, we conducted a series of studies on the properties of CYP19A1 as a candidate gene for dyslexia and related conditions. The aromatase enzyme is a member of the cytochrome P450 super family, and it serves several key functions: it catalyzes the conversion of androgens into estrogens; during early mammalian development it controls the differentiation of specific brain areas (e.g. local estrogen synthesis in the hippocampus regulates synaptic plasticity and axonal growth); it is involved in sexua…
Optical activation of TrkB neurotrophin receptor in mouse ventral hippocampus promotes plasticity and facilitates fear extinction
AbstractSuccessful extinction of traumatic memories depends on neuronal plasticity in the fear extinction network. However, the mechanisms involved in the extinction process remain poorly understood. Here, we investigated the fear extinction network by using a new optogenetic technique that allows temporal and spatial control of neuronal plasticity in vivo. We optimized an optically inducible TrkB (CKII-optoTrkB), the receptor of the brain-derived neurotrophic factor, which can be activated upon blue light exposure to increase plasticity specifically in pyramidal neurons. The activation of CKII-optoTrkB facilitated the induction of LTP in Schaffer collateral-CA1 synapses after brief theta-b…
Automated analysis of images for molecular quantification in immunohistochemistry.
The quantification of the expression of different molecules is a key question in both basic and applied sciences. While protein quantification through molecular techniques leads to the loss of spatial information and resolution, immunohistochemistry is usually associated with time-consuming image analysis and human bias. In addition, the scarce automatic software analysis is often proprietary and expensive and relies on a fixed threshold binarization. Here we describe and share a set of macros ready for automated fluorescence analysis of large batches of fixed tissue samples using FIJI/ImageJ. The quantification of the molecules of interest are based on an automatic threshold analysis of im…