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Magnetic susceptibility and ESR studies on high-spin (S=3⁄2) tetrahedral cobalt(II)–thiolate complexes were performed for A2[Co(SPh)4]; A=Me4N (1a), Et4N (1b), Ph4P (1c) and (Et4N)2[Co(SR)4]; R=C6H4-p-Me (2), C6H4-p-Cl (3), C6F5 (4). It was found that the magnitude of zero-field splitting and the anisotropy of g-factor are exceptionally large for 1c as D≈−100 cm−1, E≈0, gx≈gy<gz. This parameter set shows that Co(SPh)42− in 1c is strongly affected by an axial distortion. On the contrary, a rhombic distortion with moderate magnitude was found for 1a (D*=6.5 cm−1, E⁄D=−0.21) and 1b (D*=5.0 cm−1, E⁄D=0.19). The results for the other compounds are D*=7.0 cm−1, E⁄D=0.14 for 2, D*=12 cm−1, E⁄D=0.10 for 3, and D*=2.0 cm−1, E⁄D=0.02 for 4. Attempts were made to correlate the magnetic properties and the coordination geometry for 1a–c by use of available X-ray data. As a result, the importance of the orientation of the thiolate ligands was confirmed.

We used northern and western blotting to measure the quantity of glutamate and GABA transporters mRNA and their proteins within the hippocampal tissue of rats with epileptogenesis. Chronic seizures were induced by amygdalar injection of kainic acid 60 days before death. We found that expression of the mRNA and protein of the glial glutamate transporters GLAST and GLT-1 were down-regulated in the kainic acid-administered group. In contrast, EAAC-1 and GAT-3 mRNA and their proteins were increased, while GAT-1 mRNA and protein were not changed. We performed in vivo microdialysis in the freely moving state. During the interictal state, the extracellular glutamate concentration was increased, whereas the GABA level was decreased in the kainic acid group. Following potassium-induced depolarization, glutamate over¯ow was higher and the recovery time to the basal release was prolonged in the kainic acid group relative to controls. Our data suggest that epileptogenesis in rats with kainic acid-induced chronic seizures is associated with the collapse of extracellular glutamate regulation caused by both molecular down-regulation and functional failure of glutamate transport.

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A simple two-electrode cell for low-temperature electron spin resonance (ESR) measurements has been designed. A helical gold wire, the working electrode with large surface area (12 cm2), generated intra muros enough positive or negative ions to measure the ESR spectra of unstable radical ions at low temperatures. To test the electrolysis conditions of the cell, the ESR spectra of about 20 aromatic compounds have been observed at temperatures as low as −90 °C. It has been shown that the cell can be applicable to the compounds with half-wave potential of 1.5 to −3.7 V SCE, provided that the ions produced are not reactive. The experimental conditions of the dimer cation generation have also been checked in polar or nonpolar solvents.