ABSTRACT
Objective To research sorption of local anesthetic by fat emulsion with different content of lipid in vitro and then to discuss the mechanism of action of fat emulsion for treatment of local anesthetic toxicity. Methods 10%,20%,30% fat emulsion was added to the bupivacaine hydrochloride and ropivacaine hydrochloride.After the mixture was vortexed for 10 mins,it was vibrated in thermostatic water bath at 37 ℃ for 15 h,then centrifugated and got the aqueous phase to HPLC test.The chromatography was carried on a C18column(4.6 mm×250 mm,5 μm ),the mobile phase was composed of acetonitrile-natrium biphosphoricum(25:75),the flow rate was 1 mL·min-1,the column temperature was 30 ℃ and the detection wavelength was set at 210 nm. Results Under the condition of this test,the linear ranges and linear equations for bupivacaine hydrochloride and ropivacaine hydrochloride were 0.3-3.0 μg·mL-1,Y=0.093 6X-0.017 3(r=0.999 6),and 0.3-3.0 μg·mL-1,Y=0.086 6X-0.022 3(r=0.999 1) respectively.The lowest limit of quantitation were both 0.05 μg·mL-1(S/N>3),and the ingredients showed good relationships between the peak area and the concentration.Sample reproducibility was good because the test sample was stable in 5 h.The extraction rates of bupivacaine hydrochloride by 10%,20%,30% fat emulsion were 46.0%,70. 4%,89.2% respectively.The extraction rates of ropivacaine hydrochloride by 10%,20%,30% fat emulsion were 51.3%,71.6%, 90.7% respectively. Conclusion Electric potential and the pH value of the 10%,20%,30% fat emulsion are similar,while the particle size increase slightly.Free bupivacaine hydrochloride and ropivacaine hydrochloride can be absorbed and with the increase of fat content,the extraction of local anesthetic is increased.The mechanism of action of fat for the treatment of local anesthetic toxicity maybe related to that fat emulsions can provided lipid,so that the excessive local anesthetic or those which had already distributesd in tissue can re-dispersed in lipid,and then the plasma concentration of local anesthetic is reduced,the toxicity is also reduced.
ABSTRACT
Objective To test experimentally Fluoro-Jade B(FJB) stain method for detecting degeneration of neurons in the basal ganglia. Methods Kainic acid(KA)-lesion model by stereotaxical injection of KA into striatum of rats,MPTP-lesion model by injection of MPTP into intraperitoneal cavity of mice,as well as KA-lesion model of cultured striatal cells were firstly prepared.FJB stain dye was then used to visualize degeneration of neurons in above KA-or MPTP-lesion models. Results KA-or MPTP-induced degenerative neurons including cell bodies and processes could be clearly visualized by FJB stain dye.In the brain sections,FJB-positive stained degenerative neurons were numerously observed in the striatum of KA-lesion rats and the substantia nigra pars compacta of MPTP-treated mice,but not detected in the control animals.Moreover,degenerative neurons were also detected with FJB stain in cultured striatal neurons.Semi-quantitative analysis on percentage(?s) of FJB-positive neurons constituting total cultured striatal neurons in unit area showed that degenerative neurons of KA-lesion group (8.42?1.09)% was evidently more than that of controls (3.42?0.45)%,P
ABSTRACT
Objective To detect the location of histamine in peripheral sympathetic nerves of guinea pig. Methods Histidine decarboxylase mRNA was detected using in situ hybridization histochemistry with specific oligonucleotide probe,while histamine and tyrosine hydroxylase were detected using double labeled immunohistochemistry with anti-histamine antibody and anti-tyrosine hydroxylase antibody in the superior cervical ganglia of guinea pig. Results The histidine decarboxylase mRNA hybridization signal were detected in both of large and small cells.The TH immunoreactive substance distributed in cytoplasm steadly,but lacked in the nuclei,while the histamine immunoreactive substance distributed in cytoplasm nearby the plasmalemma.After chemical destroy of the guinea pig SCG′s neuron with 6-OHDA,the immunoreactive materials were hardly detected.Conclusion Because the histidine decarboxylase is the only enzyme which catalyzes histidine into histamine,histamine may be synthesized and coexisted with monoaminergic neurotransmitters in the superior cervical ganglia of guinea pig.