Mechanisms of bupivacaine inhibition of glutamate-induced intracellular calcium elevation in primary cultured rat hippocampal astrocytes / 药学学报

This research investigated the mechanism by which bupivacaine inhibits glutamate-induced intracellular free Ca2+ increases in primary cultured hippocampal astrocytes. Immunofluorescence was used to demonstrate the expression of metabotropic glutamate receptor (mGluR5 receptor) on neurons and astrocytes. Calcium imaging was used to measure the alteration of intracellular free Ca2+ ([Ca2+]i) in primary cultured rat hippocampal neurons and astrocytes. The animal experiments were approved by the Animal Experiments Ethical Committee of Hebei Medical University. The results showed that mGluR5 receptor was abundantly expressed in the primary cultured rat neurons and astrocytes. Bupivacaine (300 μmol·L-1) significantly inhibited 1 mmol·L-1 glutamate-induced [Ca2+]i increase in astrocytes (P < 0.01). 2-Methyl-6-(2-phenylethynyl)-pyridine (MPEP) (10 μmol·L-1) completely abolished the increase of [Ca2+]i induced by 1 mmol·L-1 glutamate in the astrocytes (P < 0.01), while the inhibitory effect on neurons was only 10%-20%. Bupivacaine (300 μmol·L-1) completely inhibited the [Ca2+]i increase induced by mGluR5 receptor agonists (RS)-3,5-dihydroxyphenylglycine (DHPG) (50 μmol·L-1) and (RS)-2-chloro-5-hydroxyphenylglycine sodium salt (CHPG) (1 mmol·L-1) in astrocytes (P < 0.01). In addition, bupivacaine inhibited the CHPG-induced [Ca2+]i increase in a dose-dependent manner in astrocytes with an IC50 of 100 μmol·L-1. The results from this study indicate that bupivacaine inhibits glutamate-induced [Ca2+]i elevation by acting on the mGluR5 receptor in primary cultured hippocampal astrocytes.

Determination of spinosin and total saponins in compound Zaoshen tablet by HPLC and UV / 药学实践杂志

Objective To establish methods for the determination of spinosin and total saponins in compound Zaoshen tablet .Methods The separation of spinosin was performed on Agilent Zorbax SB C18 column (250 mm × 4 .6 mm ,5 μm) at 30℃ with water and acetonitrile as mobile phase for gradient elution at the flow rate of 1 .0 ml/min .The detection wavelength was 335 nm .Determination of total saponins was fulfilled by column chromatography followed by UV spectrometer with vanil-lin glacial acetic acid colorimetry .The detection wavelength was 560 nm .Results Linear range of spinosin was 20-100 μg/ml (r=0 .9990) and total saponins was 40-200 μg/ml (r=1 .0000) .The average recoveries for accuracy tests were 99 .55% and 99 .85% respectively .Conclusion Those methods are accurate and reliable .They can be used for the quality control of com-pound Zaoshen tablet .