Objective To study the expression of iNOS and AChE during streptomycin ototoxicity and the correlation.Methods 16 guinea pigs were divided into 2 groups randomly:control group and SM group.SABC immunohistochemical staining and image quantitative analysis technique were used to observe the expression of iNOS and AChE and grey value analysis.ABR measurements were used to monitor the effects of ototoxity.Results After 10 days with drugs,the ABR threshold value of SM group increased more significantly than that of the control group(P

Aim To examine the apoptosis and bFGF expression on the cochlea of guinea pig after administrated streptomycin(SM) and the antagonism of Salvia Miltiorrhiza Injection(DS) on SM ototoxity.Methods Forty guinea pigs were divided into four groups,and treated with DS and SM respectively.The apoptosis and bFGF expression were examined by TdT mediated biotin dUTP nickend labeling(TUNEL) techniques and SABC immunohistochemical staining with paraffin slide.The intensity of images were stored in a computer and analyzed by the image quantitative analysis technique.Auditory brainstem response(ABR) measurement was used to detect the ototoxicity before/after the examination.Results After 10 d treated by drugs,the ABR threshold of SM increased significantly,while the DS+SM reduced more(P

A novel flow injection chemiluminescence（CL）method for the determination of loxoprofen and naproxen was proposed based on the CL system of KMnO4 and Na2SO3 in acid media.The CL intensity of KMnO4-Na2SO3 was greatly enhanced in the presence of loxoprofen and naproxen.The mechanism of the CL reaction was studied by the kinetic process and UV-vis absorption and the conditions were optimized.Under optimized conditions,the CL intensity was linear with loxoprofen and naproxen concentration in the range of 7.0×10^-8-1.0×10^-5g/mL and 2.0×10^-7-4.0×10^-6g/mL with the detection limit of 2.0×10-8g/mL and 3.0×10-8g/mL（S/N=3）,respectively.The relative standard deviations were 2.39% and 1.37% for 5.0×10^-7g/mL naproxen and 5.0×10^-7g/mL loxoprofen（n=10）,respectively.The proposed method was satisfactorily applied to the determination of loxoprofen and naproxen in pharmaceutical preparations.

Objective To investigate the expression of inducible nitric oxide synthase(iNOS) in the cochlear stria vascularis(SV) of guinea pigs after streptomycin(SM).Methods Auditory brainstem response(ABR) was used as measurement index,and combining with transmission electron microscope(TEM),immunohistochemical staining and image quantitative analysis technique, to detect iNOS expression in the cochlea stria vascularis of guinea pigs and the change of morphology after SM.Results 10 days after adminitration, ABR threshold of SM group increased more significantly than that of the control group(P

Objective To observe the effect of tetraethylplyrazine(TMP) on outward K~+ channel of outer hair cells in guinea pig cochlea.Methods 60 guinea pigs were divided into 6 groups randomly in the experiment.Auditory brainstem response was used to monitor the change of ABR thresholds and patch clamp techniques to observe the effect of TMP on outward K~+ channel.Results TMP decreased the elevated ABR threshold caused by streptomycin. The TMP increased the amplitudes of calcium sensitive potassium channels (I_ K(Ca) ) and delayed outward potassium channels (IK) of outer hair cells of guinea pig cochlea.Conclusion The study indicates that TMP may act as a protective agent against ototoxicity of streptomycin. The amplitudes of I_ K(Ca) and IK of outer hair cells are increased by the TMP,suggesting the possible mechanisms of reducing ototoxicity.

A novel flow injection chemiluminescence (CL) method for the determination of loxoprofen and naproxen was proposed based on the CL system of KMnO4 and Na2 SO3 in acid media.The CL intensity of KMnO4-Na2 SO3 was greatly enhanced in the presence of loxoprofen and naproxen.The mechanism of the CL reaction was studied by the kinetic process and UV-vis absorption and the conditions were optimized.Under optimized conditions,the CL intensity was linear with loxoprofen and naproxen concentration in the range of 7.0 × 10- 8 - 1.0 × 10 5 g/mL and 2.0 × 10 7 - 4.0 × 10 6 g/mL with the detection limit of 2.0 × 10 8g/mL and 3.0 × 10 sg/mL (S/N =3),respectively.The relative standard deviations were 2.39％ and 1.37％ for 5.0 × 10- 7 g/mL naproxen and 5.0 × 10 7 g/mL loxoprofen ( n =10),respectively.The proposed method was satisfactorily applied to the determination of loxoprofen and naproxen in pharmaceutical preparations.

AIM: To establish the cell model of hippocampal neurons impaired by the supernatant of microglia conditioned medium (MCM) induced by LPS, and to study the mechanisms of neuron damage and the protection effect of curcumin. METHODS: The microglia were activated and stimulated by LPS at concentration of 5 μg/L. The supernatant of activated MCM was used to stimulate the hippocampal neurons. The morphology of the neurons was observed under light microscope and the survival rate was detected by MTT. The availability of respiration in the hippocampal neurons was determined by detecting the ratio of lactic acid/pyruvic acid, and the expression of 3 types of 1,4,5-inositol triphosphate (IP3R1, IP3R2, IP3R3) was detected by RT-PCR. RESULTS: The hippocampal neurons were damaged severely by the supernatant of activated MCM, and the morphology of the neurons changed significantly. Compared to control group, the ratio of lactic acid/pyruvic acid in MCM group was elevated and the expression levels of IP3R1 and IP3R3 in the hippocampal neurons were significantly increased. The ratio of lactic acid/pyruvic acid and the expression of IP3R1 in curcumin+MCM group were evidently lower than those in MCM group. However, no effect of curcumin on IP3R3 expression was observed, the changes of neural morphology was also ameliorated in curcumin+MCM group. CONCLUSION: Curcumin protects rat hippocampal neurons from damage induced by LPS-induced microglia condition medium.

BACKGROUND: Ligustrazine possesses the effect to reduce ototoxicity of gentamicin, whether does it antagonize the ototoxicity of gentamicin through influencing the expression of heat shock protein (HSP) 70 in cochlea of guinea pigs with gentamicin induced ototoxicity? BJECTIVE: To investigate the effect of ligustrazine on the expression of HSP70 in cochlea of guinea pigs with gentamicin induced ototoxicity through immunohistochemistry and image analysis technique in combination with the measurement of auditory brainstem response (ABR).DESIGN: A randomized controlled study, and linear correlation analysis. ETTING: Physiological Department of Shenyang Medical College and Audiological Laboratory of China Medical University.MATERIALS: Totally 40 white and red-eye healthy guinea pigs of lean grade and with keen auricle reflect, weighing 200 - 250 g, of either gender, were at random divided as gentamicin group, ligustrazine + gentamicin group, ligustrazine group, and normal control group, with 10 in each group.METHODS: Ligustrazine injection 140 mg/kg was intraperitoneally at the left side given for animals in ligustrazine + gentamicin group, and at the same time gentamicin sulfate injection 100 mg/kg was given intraperitoneally at the right side. The same dosage of gentamicin sulfate injection was intraperitoneally given for animals in gentamicin group. The same dosage of ligustrazine was intraperitoneally give for animals in ligustrazine group. The normal saline 2.5 mL/kg was intraperitoneally given for animals in normal control group. Administration was consecutively given for 10 days for each group, once a day. The body mass was measured every day for regulating the dosage. Before starting and after finishing the administration, the thresholds of ABR of all animals in each group were measured respectively. After finishing administration, all animals in each group were put to death, and the conditions of expressions of HSP70 in cochlea of guinea pigs were investigated by SABC immunohistochemistry and image analysis technology.MAIN OUTCOME MEASURES: ① the thresholds of ABR of all animals in each group; ② expressions of HSP70 in cochlea of guinea pigs in each group.RESULTS: ① The thresholds of ABR of guinea pigs: The thresholds in ligustrazine + gentamicin group and gentamicin group were obviously higher than that in normal control group [(21.09±4.50) dBnHL, (36.55±6.13)dBnHL, (2.50±2.75) dBnHL, t=15.764-22.665, P ＜ 0.001]. The threshold in ligustrazine + gentamicin group was obviously lower than that in gentamicin group (t=9.092, P ＜ 0.001). ② The expressions of HSP70 in each part of cochlea of guinea pigs: The mean gray values of cellular HSP70 positive reaction products in Corti's organ, vascular stria and spiral ligament, spiral limbus and spiral ganglion in gentamicin group were lower than those in normal control group (88.24±4.34, 96.85±1.05; 121.24±0.92,128.76±1.59; 96.15±1.10, 98.78±0.54; 117.73±1.18, 120.51±0.80, t=6.097-18.307, P ＜ 0.001). The mean gray values of cellular HSP70 positive reaction products in ligustrazine + gentamicin group were lower than those in gentamicin group (92.53±2.25, 88.24±4.34; 125.20±1.43, 121.24±0.92;98.71±0.91, 96.15±1.10, 118.91±0.46, 117.73±1.18, t=3.925-10.415, P＜ 0.001).③ The mean gray value of cellular HSP70 positive reaction products in each part of cochlea of guinea pigs was highly correlated with the threshold of ABR (r=-0.814 1 to -0.984 1, P ＜ 0.001).CONCLUSION: Ligustrazine could reduce the threshold of ABR and the expression of HSP70 in cochlea with gentamicin toxicosis so as to relieve gentamicin ototoxic injury, hence improving auditory function.

Objective To develop a rapid, simple and sensitive chemiluminescence method for the determination of three β-blockers (bisoprolol, atenolol and propranolol). Methods The chemiluminescence of cerium (Ⅳ)-sulfite system was obviously sensitized by adding anyone of three β-blockers in acid media. A new chemiluminescence method was set up by combining with flow-injection technique and used to determine the three β-blockers. Results Good linear ranges were obtained at the concentrations of 2.0×10-7g/mL-4.0×10-5g/mL, 1.0×10-7g/mL-3.0×10-5g/mL and 7.0×10-7g/mL-1.0×10-5g/mL, respectively, with the detection limits of 5.0×10-8g/mL, 7.0×10-8g/mL and 5.0×10-8g/mL (S/N=3), respectively, and the relative standard deviations for 11 times consecutive injections of 1.0×10-6g/mL bisoprolol, atenolol and propranolol were 3.57%, 2.21% and 2.26%, respectively. Conclusion The developed method is sensitive, accurate, rapid and of low cost. And it can be applied to determine bisoprolol, atenolol and propranolol in pharmaceutical preparations.

Objective To provide a better reference for the quality control of Nujin Pian by establishing the method for the determination of paeonol in Nujin Pian by HPLC. Methods HPLC was used Agilent XDB C18 column (4.6 mm×150 mm, 4.6 μm), mobile phase was composed of methanol-water (45∶55). The flow rate was 1.0 mL/min with detection wavelength at 274 nm and column temperature at 40 ℃. Results The regression equation of paeonol was Y=7×107X-16 965, r 2=0.999 8 (n=6). The linear range of paeonol was 0.003 8-0.38 μg. The average recovery rate was 99.7%, and RSD was 1.56% (n=6). Conclusion The method is simple, fast and accurate with good reproducibility. It can provide reference for the quality control of Nujin Pian.