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The aim of this study was to examine the antidepressant-like responses to vitamin D3 (VD3) subcutaneous (s.c.) supplementation (1.0, 2.5, and 5.0 mg/kg) in middle-aged long-term ovariectomized (OVX) rats treated with a low dose of 17β-estradiol (17β-E2) (0.5 μg/rat, s.c.) exposed to the chronic unpredictable mild stress (CUMS). Sucrose preference (SPT), forced swimming (FST), and open-field (OFT) tests were performed to measure anhedonia, depressionlike state, and locomotor/grooming activities, respectively. Glial cell line-derived factor (GDNF) levels in the hippocampus of middle-aged long-term OVX rats following CUMS treated with VD3 were measured using ELISA and Western blotting. The serotonin (5-HT) and 5-hydroxyindoleacetic acid (5-HIAA) concentrations in the hippocampus were detected by high performance liquid chromatography (HPLC). The findings demonstrated that VD3 (1.0 mg/kg, s.c.) in a combination with a low dose of 17β-E2 increased sucrose consumption in the SPT and decreased depression-like behavior in the FST of middle-aged long-term OVX rats exposed to CUMS. This dose of VD3 elevated hippocampal GDNF protein expression and increased 5-HT/5-HIAA levels in middle-aged long-term OVX rats plus 17β-E2 compared to the middle-aged OVX rats plus 17β-E2 with CUMS. The other two doses of VD3 (2.5 and 5.0 mg/kg, s.c.) failed to modify both GDNF protein levels and 5-HT turnover in the hippocampus of middle-aged long-term OVX rats treated with 17β-E2 exposed to CUMS. Thus, treatment with a low dose of VD3 (1.0 mg/kg, s.c.) in a combination with a low dose of 17β-E2 enhanced antianhedonic-/antidepressant-like effects of both substances in middle-aged long-term OVX rats exposed to CUMS.

The article presents a brief history of the formation of scientific ideas about kidney physiology and the mechanisms of water-salt metabolism regulation in Novosibirsk, as well as the role of some physiologists in the development of these views. The beginning of the development of renal physiology in Novosibirsk was the idea by A.G. Ginetsinsky about the reflex osmoregulatory system of the organism, that was developed by his students (L.K. Velikanova, Ya.D. Finkinstein, L.N. Ivanova, Yu.V. Natochin, L.I. Kurduban). Later on, the veiws about the ion-regulating mechanisms and age-specific features of their formation in the ontogenesis of humans and animals have been formed (A.Ya. Terner, R.I. Aizman, I.V. Pantyukhin). The role of interconnections in this direction between the researchers from Novosibirsk and scientists from the USA (L. Rabinowitz), Sweden (A. Aperia, G. Celsi), Israel (H. Garty, S. Karlish) and others were shown. Knowledge of the history of the development of renal physiology in different countries and the results of cooperation between researchers play an important role in understanding the development prospects of this scientific area.

Computational models for two neuron/astrocyte networks are developed to explore mechanisms underlying the astrocytes’ role in maintaining neuronal firing patterns. For the first network, a single neuron receives periodic excitatory inputs at varying frequencies. We consider the role played by several astrocytic dendritic processes, including the Na+-K+ ATPase pump, K+  channels and gap junctions in maintaining extracellular ion homeostasis so that the neuron can faithfully sustain spiking in response to the excitatory input. The second network includes two neurons coupled through mutual inhibitory synapses. Here we consider the role of astrocytic dendritic processes in maintaining anti-phase or synchronous oscillations. Dynamical systems methods, including bifurcation theory and fast/slow analysis, is used to systematically reduce the complex model to a simpler set of equations. In particular, the first network, consisting of differential equations for the neuron and astrocyte membrane potentials, channel state variables and intracellular and extracellular Na+ and K+ concentrations, is reduced to a one dimensional map. Fixed points of the map determine whether the astrocyte can maintain extracellular K+ homeostasis so the neuron can respond to periodic input. 

In this study we examined the intersection of two molecular pathways both known to regulate dentate development – the Emx2 transcription factor and the Sonic Hedgehog (Shh) morphogenic scignaling pathway. We confirmed that Emx2 mutant mice have a markedly reduced dentate gyrus and studied evidence of changes in Shh signaling and Shh expression in these mutants. Our results indicate that loss of Emx2 affects the numbers and distribution of Gli+ ventrally derived dentate neural stem cells that are responsible for populating the perinatal dentate gyrus. Accompanying this, we find that Emx2 mutants have reduced expression of Shh in the amygdalo-hippocampal region. In addition, there are ectopic Shh responsive progenitors that fail to properly populate the dentate. Taken together our results indicate that Emx2 regulates dentate development in part by altering availability and signaling of Shh.

The convoluted human cerebral cortex is one of the key features that allows for an increased neuronal density packing essential for the complex cognitive and socioemotional behaviours man possesses. Nevertheless, the underlying mechanisms involved in cortical folding remained a both intriguing and functionally important enigma. A crucial component known to be involved in the formation and maintenance of all tissues is the extracellular matrix (ECM), providing scaffolds which tie tissues and organs in place. The composition of the ECM in both developing and mature structures is constantly remodelled, degraded and secreted by numerous types of cells, and its role as a source of growth factors and signalling in morphogenesis, migration, and proliferation is increasingly appreciated. Evidence for the differential expression of ECM during gyrification pinpoints its potentially fundamental role in shaping the folds of the cerebral cortex through both mechanical and molecular configurations. This review aims at addressing key ideas, potential directions and discoveries that highlight biomechanics of the ECM during the construction of the cortex cerebral gyrification.