In the title sinomenine derivative, C(26)H(28)FNO(4)·1.5H(2)O, the dihedral angle between the two aromatic rings is 55.32 (6)°. The N-containing ring has an approximate chair conformation, while other two rings have approximate envelope and half-chair conformations. One water mol-ecule is located on a twofold symmetry axis. In the crystal, the water mol-ecules form O-H⋯O and O-H⋯N hydrogen bonds, bridging symmetry-related main mol-ecules.

The title compound, C(26)H(30)ClNO(4), a sinomenine derivative, has five six-membered rings, two of which are aromatic, with a dihedral angle of 34.13 (20)° between these. The N-containing ring and the fourth ring exhibit chair conformations, while the fifth ring approximates an envelope conformation. A single inter-molecular O-H⋯N hydrogen-bonding inter-action gives a one-dimensional chain structure which extends along the a axis. The absolute configuration for the mol-ecule has been determined.

In the title compound, C(26)H(31)NO(4), a sinomenine derivative, the angle between the two aromatic rings is 53.34 (4)°. The N-containing ring is in a chair conformation, while the other two non-planar rings are in a half-boat conformation. In the crystal, mol-ecules are linked by O-H⋯N inter-actions into a C(8) chain along [100].

Intermittent hypoxia has been found to prevent brain injury and to have a protective role in the CNS. To address the possible causes of this phenomenon, we made investigative effort to find out whether intermittent hypoxia affects neurogenesis in the adult rat brain by examining the newly divided cells in the subventricular zone (SVZ) and dentate gyrus (DG). The adult rats were treated with 3000 and 5000 m high altitude 4 h per day for 2 weeks consecutively. 5-Bromo-2-deoxyuridine-5-monophosphate (BrdU) immunocytochemistry demonstrated that the BrdU-labeled cells in the SVZ and DG increased after 3000 and 5000 m intermittent hypoxia. The number of BrdU-labeled cells in the SVZ returned to normal level 4 weeks following intermittent hypoxia. However, the BrdU-labeled cells in the DG had a twofold increase 4 weeks subsequent to intermittent hypoxia. From these data, we conclude that intermittent hypoxia facilitates the proliferation of neural stem cells in situ, and that the newly divided cells in the SVZ and DG react differently to hypoxia. We are convinced by these findings that the proliferation of neural stem cells in SVZ and DG may contribute to adaptive changes following intermittent hypoxia.

It is known that hypoxic preconditioning (HP, a brief period of sublethal hypoxia) provides neuroprotection against subsequent severe anoxia, but the mechanisms of this increased tolerance have not been fully elucidated. A hypoxic preconditioning model was established by exposing a 4-day hippocampal culture to 1% O(2) for 20 min/day for 8 days. The preconditioning significantly decreased the number of apoptotic neurons at reoxygenation 24 h after 4 h of severe anoxia (0% O(2)). Further study demonstrated that the degradation of mitochondrial membrane potential (MMP) was greatly inhibited and the expression of B-cell lymphoma protein-2 (Bcl-2) was increased considerably after severe anoxia in the HP groups. These results indicate that the increased anoxic tolerance, which is induced by HP in cultured hippocampal cells, may be correlated with Bcl-2 overexpression and enhanced stability of MMP, which ultimately reduces apoptosis 24 h after reoxygenation.

The effects of hypoxic preconditioning (HP) on changes in mitochondrial membrane potential (MMP) and Bcl-2 expression in cultured hypothalamic neurons after severe anoxia were investigated. In the HP group, hypothalamic neurons, after a 4-day culture, were preconditioned daily under a hypoxic condition (1% O(2), 10 min) for 8 days; subsequently, the HP neurons and those in the control group (similarly cultured, but without HP) were exposed to 6 h of severe anoxia (0% O(2)). The preconditioned neurons had a higher survival rate and a lower lactate dehydrogenase leakage, compared with the control group. Although HP did not prevent the degradation of MMP during severe hypoxia, preconditioned neurons exhibited a higher level of MMP than that of the control group. Increased expression of Bcl-2 was also observed in the preconditioned hypothalamic neurons. These results suggest that HP enhances the hypoxic tolerance of hypothalamic neurons, and the underlying mechanisms may be related to the increased stability of MMP and the overexpression of Bcl-2 induced by HP.

OBJECTIVE: To study if monoclonal antibody against human NMDA receptor key subunit (NR1) may protect neurons from excitotoxicity. METHODS: We cultured primary hippocampal neurons from 10 newborn rats and made the glutamate excitotoxicity model, examined the ratio of surviving neuron (Trypan blue dye staining) and LDH assay to study the protective effects of mAbN1, There were 2 plates in parallel per group, the experiments were repeated 4 times. RESULTS: 0.3 micro mol/L mAbN1 could protect cultured hippocampal neurons from neuroexcitotoxicity induced by 500 micro mol/L glutamate with increased survival rate 35%. Epitope peptide could block the protection of mAbN1, which suggests that the protection of mAbN1 is specific. CONCLUSION: mAbN1 is a novel NMDAR blocker with in vitro neuroprotective activity which may provide a basis for antibody therapy of neuroexcitotoxicity.

OBJECTIVE: To investigate the damage of anoxia on the cultured rat's cortical neurons and the protective effects of naloxone. METHODS: Cortical neurons cultured for 12 days were randomly divided into three groups: control, anoxic group and anoxic group plus naloxone treated. Cortical neurons were exposed to anoxic environment for 6 hours and then cultured for 24 hours under normoxic condition. The apoptosis of neurons was detected with the method of TdT-mediated dUTP nick end labeling (TUNEL) and the apoptotic rate of neurons was measured using flow cytometry. RESULTS: Anoxia could lead to increasing apoptosis and death of rate cortical neurons. Naloxone could reduce neuron apoptosis. There was a significant difference between the anoxic group and anoxic group plus naloxone (P<0.01). CONCLUSION: Naloxone can ameliorate the toxicity damage of neurons caused by anoxia through reducing neuron apoptosis, which suggests that naloxone could protect rat's cortical neurons from damage under anoxia condition.

The effect of CoCl(2) pretreatment on glucose transport activity of cultured newborn rat hip- pocampal neurons and its role in neuronal hypoxic tolerance were observed. The results showed that the 2-deoxy-D-[1-(3)H ]glucose uptake rate and the mRNA expressions of glucose transporters (GLUT1 and GLUT3) in the hippocampal neurons were significantly increased after a 24-hour pretreatment with CoCl(2). The cell injury induced by 6-hour or 8-hour hypoxic exposure was also greatly reduced by CoCl(2) pretreatment. The protective effect of CoCl(2) on the neurons was largely abolished by cytochalasin B, a specific inhibitor of glucose transporters. The results suggest that CoCl(2) can increase mRNA expressions of GLUT1 and GLUT3 and glucose transporter activity of the neurons, which may be an important mechanism for the increased tolerance of the neurons to hypoxia.

The purpose of the present study was to determine the effects of recombinant human interleukin-6 (rhIL-6) on the Bcl-2 and Bax expression and apoptosis after anoxia-reoxygenation in cultured rat hippocampal neurons. The control and rhIL-6 treated hippocampal neurons cultured for 12 d were exposed to anoxia environment (90% N2+10% CO2) for 2 and 4 h and then were reoxygenated for 24 and 72 h. The expression of Bcl-2 and Bax was revealed immunocytochemically using the antiserum against Bcl-2 and Bax. The apoptosis was examined by the terminal deoxynucleotidyl transferase-mediated biotinylated deoxyuridine triphosphate nickel end labeling (TUNEL) method and flow cytometric analysis. The results showed that in cultured hippocampal neurons the Bcl-2 expression decreased while Bax expression and the percentage of apoptotic neurons increased after anoxia-reoxygenation compared with those before anoxia. In comparison with the control, after anoxia-reoxygenation the Bcl-2 expression in hippocampal neurons was higher than that in rhIL-6 group; however the Bax expression and the percentage of the apoptosis were decreased in rhIL-6 group. It is suggested that rhIL-6 may play a role in protecting neurons from the damage induced by anoxia-reoxygenation.