ABSTRACT
<p><b>AIM</b>To study the effects of sodium salicylate on the expression of GABAalpha NR1 and hearing response properties of inferior colliculus neurons in mice.</p><p><b>METHODS</b>Thirty-six kunming mice were divided into three groups (A, B, C,). The expression of GABAalpha NR1 were measured by using RT-PCR. The intensity-rates functions, intensity-latency functions and frequency-turning curves were recorded by extracellular electrophysiological recording techniques.</p><p><b>RESULTS</b>(1) The expression of GABAalpha mRNA of B group was decreased remarkably than the control group (A group, P < 0.05), there weren't noticeable differences between A group and C group (P > 0.05). The expression of NR1 mRNA of B group was increased remarkably than the control group (A group, P < 0.01), there were noticeable differences between A group and C group P < 0.05). (2) The intensity-rates functions, intensity-latency functions were monotonic while the frequency-turning curves were more broad when sodium salicylate was given. (3) The intensity-rates functions, intensity-latency functions were non-monotonic while the frequency-turning curves were sharpened after lidocaine was given.</p><p><b>CONCLUSIONS</b>(1) The results suggested that administration of sodium salicylate decreased the expression of GABAalpha while increased the expression of NR1mRNA. (2) The intensity-rates functions, intensity-latency functions were monotonic, the frequency-turning curves were more broad when salicylate was given and the changes above could be reversed by given lidocaine.</p>
Subject(s)
Animals , Mice , Acoustic Stimulation , Inferior Colliculi , Metabolism , Physiology , Mice, Inbred Strains , Neurons , Metabolism , Physiology , Receptors, N-Methyl-D-Aspartate , Metabolism , Sodium Salicylate , Pharmacology , gamma-Aminobutyric Acid , MetabolismABSTRACT
The effects of neuroglobin (NGB) gene transfer in vivo mediated by GeneJamer on the hearing response properties of the inferior colliculus (IC) neurons in mice after administration of sodium salicylate were studied. Forty-eight Kunming mice were divided into 4 groups (n=12 in each group): Group A1 (negative control);Group A2 (positive control);Group B, sodium salicylate (450 mg/kg every day) + pEGFP-C1;Group C, sodium salicylate (450 mg/kg every day) + pEGFP-NGB. The GeneJamer and pEGFP-NGB were mixed and injected into IC neurons in mice. The expression of NGB mRNA and protein of IC neurons in mice was detected by using RT-PCR and Western blot methods. The intensity-rate functions, intensity-latency functions and frequency-turning curves in IC neurons were recorded by extracellular electrophysiological recording techniques and the effects of pEGFP-NGB transfer following injection of sodium salicylate on them were studied. It was found that: (1) The GeneJamer-mediated pEGFP-NGB could be effectively transferred into the IC brain tissues in mice and NGB could be expressed intensively. (2) The intensity-rate functions of IC neurons were raised after administration of sodium salicylate. The non-monotonic styles of intensity-rate functions in groups A1, A2 and C were accounted for 74.6%, 72.2 %, 59.3 %, respectively, and the function in group B for 47%. There were significant differences between group B and groups A1, A2 or C (P<0.01, P<0.01, P<0.05). (3) The intensity-latency functions in IC neurons were reduced after administration of sodium salicylate. The non-monotonic styles of intensity-latency functions in groups A1, A2 and C were accounted for 3.2 %, 5.1 %and 21 %, respectively, and that in group B for 45.5 %. There were significant differences between group B and groups A1, A2 or C (P<0.01, P<0.01, P<0.05, respectively). (4) The frequency-turning curves in groups A1 and A2 were sharpened. In 72 acoustic neurons recorded in the group B, the frequency-turning curves from 53 neurons were broadened while those of the rest were sharpened. In group C the frequency-turning curves recorded from 12 of 67 acoustic neurons were broadened while those of the remaining were sharpened. These results suggest that in vivo transfer of NGB gene is highly expressed in IC neurons in mice. In vivo transfer of NGB gene reverses the change of intensity-rate functions, intensity-latency functions and the code styles after administration of sodium salicylate in IC neurons in mice.
ABSTRACT
<p><b>OBJECTIVE</b>To construct the adenoviral vector containing human Bcl-2 gene and to study the expression of the gene in the spiral ganglion cells (SGC) in vitro.</p><p><b>METHODS</b>Human Bcl-2 cDNA obtained from the plasmid pUC-CAGGS/Bcl-2 was cloned into the plasmid pAdTrack-CMV. Then, pAdTrack/Bcl-2 was cotransferred with adenoviral backbone vector into E. coli strain BJ5183. The recombinant adenoviral plasmid was identified by restriction analysis with Pac I and transfected into HEK293 cells to package and amplify recombinant adenovirus particles which would be identified by Electron microscope. After the adenovirus infected the rat spiral ganglion cells, the expression of Bcl-2 gene was detected by Western Blot and RT-PCR.</p><p><b>RESULTS</b>The recombinant AdEGFP/Bcl-2 plasmid was correctly constructed and confirmed by restriction endonuclease analysis. The viral particles in HEK293 cells were identified by Electron microscope. RT-PCR and Western blot showed that Bcl-2 gene was exactly transcripted and expressed in transgene SGC.</p><p><b>CONCLUSIONS</b>The method based on homologous recombination in bacteria is simple and high efficient. The recombinant adenoviral vector containing human Bcl-2 cDNA was constructed and the transgene SGC expressed human Bcl-2 gene in vitro successfully. It provided foundation for the further study of protection for the impaired SGC by hBcl-2 gene.</p>