I-M Johansson

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Housing rats in an enriched environment improves functional outcome after ischemic stroke, this may reflect neuronal plasticity in brain regions outside the lesion. Which components of the enriched environment that are of greatest importance for recovery after brain ischemia is uncertain. We have previously found that enriched environment and social(More)
The progesterone metabolite allopregnanolone, like benzodiazepines, reduces learning and impairs memory in rats. Both substances act as GABA agonists at the GABA-A receptor and impair the performance in the Morris water maze test. Women are during the menstrual cycle, pregnancy, and during hormone replacement therapy exposed to allopregnanolone or(More)
Steroid hormones are vital for the cell life and affect a number of neuroendocrine and behavioral functions. In contrast to their endocrine actions, certain steroids have been shown to rapidly alter brain excitability and to produce behavioral effects within seconds to minutes. In this article we direct attention to this issue of neuroactive steroids by(More)
Housing rats in an enriched environment after focal brain ischemia improves functional outcome without changes in infarct volume, suggesting neuroplastic changes outside the lesion. In this study, permanent occlusion of the middle cerebral artery was followed by housing in an enriched or a standard environment. Nerve growth factor-induced gene A and(More)
This study aimed at evaluating changes in expression of immediate early genes in a new photothrombotic focal ischemia model that exhibits late spontaneous reperfusion and morphological restoration in the region-at-risk within the cerebral cortex. Gene expression was studied with Northern blots, in situ hybridization and immunohistochemistry. At early time(More)
Female ovarian steroids influence mood and cognition, an effect presumably mediated by the serotonergic system. A key receptor in this interplay may be the 5-HT(1A) receptor subtype. We gave adult ovariectomized female rats subcutaneous pellets containing different dosages of 17 beta-estradiol alone or in combination with progesterone, or placebo pellets,(More)
Some women have negative mood symptoms, caused by progestagens in hormonal contraceptives or sequential hormone therapy or by progesterone in the luteal phase of the menstrual cycle, which may be attributed to metabolites acting on the GABA-A receptor. The GABA system is the major inhibitory system in the adult CNS and most positive modulators of the GABA-A(More)
Adult male rats were treated with the antidepressant drug amitriptyline for 21 days and the expression of specific transcription factors was examined. NGFI-A mRNA expression was increased in the hippocampus and in the cerebral cortex. MR mRNA was increased in the hippocampus while GR mRNA was increased in selective hippocampal regions. There was no change(More)
AIM The roles of alpha-subunits on the gamma-aminobutyric acid (GABA)-site antagonism and pentobarbital actions were examined in rat recombinant GABA(A) receptors in Xenopus oocytes. METHODS Experiments were performed with binary and ternary GABA(A) receptors containing alpha1-, alpha4- or alpha5-subunit by the two-electrode voltage-clamp technique. (More)
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