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T-type calcium channels (T-channels) are critical for regulating neuronal excitability. Oestrogen alters neuronal excitability by modulating the expression of T-channels. The lateral habenula (LHb), as a link between the limbic system and midbrain structures, expresses T-channels and ERs. However, little is known about the role of oestrogen with respect to modulating T-channels in the LHb. In the present study, we investigated the distribution of T-channels in 3 LHb subregions (rostral, middle and caudal) in normal female rats. Next, we analysed the influence of 17β-oestradiol (E2 ) on T-channels in the LHb in ovariectomised (OVX) rats (oil and E2 groups) using whole-cell patch clamp recording and a real-time polymerase chain reaction (PCR). In normal rats, the results obtained showed that the peak of T-type calcium current (IT ) was -474.61 ± 48.33 pA and IT density was -29.11 ± 1.93 pA/pF. The IT peak and IT density on LHb neurones gradually decreased across the rostrocaudal axis. The neuronal firing pattern varied depending on the location: burst firing was dominant (53.85%) in the rostral LHb, whereas tonic firing was dominant (79.31%) in the caudal LHb. In OVX rats, real-time PCR analysis revealed that E2 treatment decreased Cav3.3 mRNA expression in the caudal LHb. Patch clamp recording showed that E2 treatment decreased the peak IT and also reduced the low-threshold spikes (LTS) number, amplitude and width of LTS in the caudal LHb. Taken together, the results obtained in the present study suggest that E2 may inhibit T-channel activity by selectively down-regulating Cav3.3 calcium channel in the caudal LHb, leading to reduced the possibility of burst firing.

Two new indium selenides [In(en)2Se]2·2I (1) and [In(teta)Se]2·2I (2) (en = ethylenediamine, teta = triethylenetetramine) were obtained under mild solvothermal conditions and structurally characterized. Compounds 1 and 2 consist of unusual organic hybrid indium selenide cations and I− anions. These ions are assembled to two different supramolecular structures by N-H···I and N-H···Se H-bonds, namely extended 3-D network structure for 1 and extended sheet structure for 2. The optical band gaps of 2.92 eV for 1 and 3.15 eV for 2 were derived from optical absorption spectra. The thermal stability of 1 and 2 was investigated by thermogravimetric measurements.

A low temperature solvothermal method has been successfully used for preparation of two semiconductor compounds CuSbQ{sub 2} (Q=S(1), Se(2)) by the reactions of Cu, Sb and S(or Se) powders in 1,2-diaminopropane at 160 deg. C for 10 days. The crystal structure of 2 was determined first time using single crystal X-ray diffraction analyses. The structures of 1 and 2 are discussed in the view of covalent bonds and weak interactions. Double CuSbQ{sub 2} layers are assembled to a 3-D network structure by Cu...Sb and Q...Sb secondary bonds. In contrast with the isostructure of the two materials, the crystal morphology of them is quite different, brick-like crystals for CuSbS{sub 2} and plank-like crystals for CuSbSe{sub 2}. The phenomenon is related to their different inter-planar interactions. Semiconductor properties of the microcrystal samples are measured and the band gaps of 1 and 2 are 1.38 and 1.05 eV, respectively. - Graphical abstract: Two isostructural compounds, CuSbQ{sub 2} (Q=S, Se), display different morphologies in crystals, which is explained by comparing the strength of the interlayer interactions based on the crystal structure data.

The title compound, catena-poly[[chloridotetrakis(ethylenediamine-kappa(2)N,N')samarium(III)] [indium(III)-di-mu-tellurido-indium(III)-di-mu-tellurido]], {[SmCl(C(2)H(8)N(2))(4)][In(2)Te(4)]}(n), consists of a one-dimensional sinusoidal {[InTe(2)](-)}(n) anionic chain and [SmCl(en)(4)](2+) cations (en is ethylenediamine). The only other previously reported lanthanide analogue, viz. [LaCl(en)(4)][In(2)Te(4)], contains more usual linear one-dimensional {[InTe(2)](-)}(n) anion chains [Chen, Li, Chen & Proserpio (1998). Inorg. Chim. Acta, 273, 255-258]. The one-dimensional polymeric {[InTe(2)](-)}(n) chain is built of InTe(4) tetrahedra sharing opposite edges. The Sm(III) ion in the [SmCl(en)(4)](2+) cation is nine-coordinated by eight N atoms from four bidentate en molecules and by one chloride ion to form a monocapped square-antiprismatic geometry. The presence or absence of N-H...Cl hydrogen bonding is shown to affect the conformation of the anion.

Two new indium selenides [In(en)2Se]2·2I (1) and [In(teta)Se]2·2I (2) (en = ethylenediamine, teta = triethylenetetramine) were obtained under mild solvothermal conditions and structurally characterized. Compounds 1 and 2 consist of unusual organic hybrid indium selenide cations and I− anions. These ions are assembled to two different supramolecular structures by N-H···I and N-H···Se H-bonds, namely extended 3-D network structure for 1 and extended sheet structure for 2. The optical band gaps of 2.92 eV for 1 and 3.15 eV for 2 were derived from optical absorption spectra. The thermal stability of 1 and 2 was investigated by thermogravimetric measurements.

Coordination of unsaturated [In(amine)]3+ onto indium telluride structure, where the complex ion has higher positive charge, not only forms an organic−inorganic hybrid polymeric structure, but also offers an indium telluride with positive charge. Based on this strategy, cationic networks of metal chalcogenide may be expected.