[Protective effects of liquid extract of Lishi No.5 formula against excitatory amino acid damage of neurons].

OBJECTIVE: To investigate the effect of liquid extract of Lishi No.5 formula in protecting the neurons from excitatory amino acid injury. METHODS: Cultured neonatal SD rat hippocampal neurons were treated with 300 micromol/L NMDA and 5 micromol/L glycine for 10 min, and the conditioned culture medium was replaced by normal culture medium. After cell culture for 18 h, MTT assay and Hoechst33258 staining were performed to examine the cell survival rate and cell apoptosis, respectively. Intracellular free calcium concentration was assayed by image analysis of the calcium signals with confocal microscope and Fluo-3/AM indicator. RESULTS: The survival rate of the cultured cell was significantly decreased in response to treatment with 300 micromol/L NMDA and 5 micromol/L glycine, but the effects were obviously reversed by treatment with 0.5 mg/ml liquid extract from Lishi No.5 formula. Intracellular free calcium concentration was significantly increased by 10 micromol/L NMDA, which was remarkably inhibited by the liquid extract. The effects of NMDA on intracellular free calcium was abolished by pretreatment of the cells with MK-801 for 10 min, whereas the liquid extract significantly lowered the antagonizing effect of MK-801. CONCLUSION: Lishi No.5 formula protects the neurons from toxicity by excitatory amino acids possibly by alleviating intracellular free calcium overload induced by these amino acids.

[The effect of lishi No.5 formula on the growth of human neuroblastoma cell line SY5Y].

OBJECTIVE: To investigate the effect of Lishi No.5 formula on the growth of human neuroblastoma cell line SY5Y and find out the most effective drug dose. METHOD: SY5Y cells were administrated by Lishi No.5 formula in different concentration. MTT metabolic rate was measured as the cell survival rate, then the dose-effect curve was made. LDH leakage rate, axonal length and area of cell body were used as the indicators. RESULT: In 0.125-0.75 g x L(-1) Lishi No. 5 formula could increase the cell survival rate and MTT metabolic rate, decreased LDH leakage rate, and enhance axonal length and area of cell body, compared with control group. CONCLUSION: Lishi No.5 formula has the neurotrophic effect and can induce the survival of neuron.

Atmospheric transport and accumulation of organochlorine compounds on the southern slopes of the Himalayas, Nepal.

Studies have been devoted to the transport and accumulation of persistent organic pollutants (POPs) in mountain environments. The Himalayas have the widest altitude gradient of any mountain range, but few studies examining the environmental behavior of POPs have been performed in the Himalayas. In this study, air, soil, and leaf samples were collected along a transect on the southern slope of the Himalayas, Nepal (altitude: 135-5100 m). Local emission occurred in the lowlands, and POPs were transported by uplift along the slope. During the atmospheric transport, the HCB proportion increased from the lowlands (20%) to high elevation (>50%), whereas the proportions of DDTs decreased. The largest residue of soil POPs appeared at an altitude of approximately 2500 m, and may be related to absorption by vegetation and precipitation. The net deposition tendencies at the air-soil surface indicated that the Himalayas may be a 'sink' for DDTs and PCBs.