RESUMO
A fast,reliable,and cost-effective liquid chromatography-tandem mass spectrometry method was established to determine the effects of the traditional Chinese medicine employed to treat coronavirus disease 2019,namely,Lianhua Qingwen granules,Huoxiang Zhengqi capsules,Jinhua Qinggan granules,Shufeng Jiedu capsules,and Angong Niuhuang pills,on the pharmacokinetics of lopinavir/ritonavir in rats.Blood samples were prepared using the protein precipitation method and atazanavir was selected as the internal standard(IS).Separation was performed on an Agilent ZORBAX eclipse plus C18(2.1 mm x 50 mm,1.8 μm)column using acetonitrile and water containing 0.1％formic acid as the mobile phase for gradient elution.The flow rate was 0.4 mL/min and the injection volume was 2 μL Agilent Jet Stream electrospray ionization was used for mass spectrometry detection under positive ion multiple reaction monitoring mode at a transition of m/z 629.3→447.3 for lopinavir,m/z 721.3→296.1 for rito-navir,and m/z 705.4→168.1 for the IS.The method showed good linearity in the concentration range of 25-2500 ng/mL(r=0.9981)for lopinavir and 5-500 ng/mL(r=0.9984)for ritonavir.The intra-day and inter-day precision and accuracy were both within±15％.Items,such as dilution reliability and residual effect,were also within the acceptable limits.The method was used to determine the effects of five types of traditional Chinese medicines on the pharmacokinetics of lopinavir/ritonavir in rats.The pharmaco-kinetic results showed that the half-life of ritonavir in the groups administered Lianhua Qingwen granules and Huoxiang Zhengqi capsules combined with lopinavir/ritonavir was prolonged by approx-imately 1.5-to 2-fold relative to that in the control group.Similarly,the pharmacokinetic parameters of lopinavir were altered.Overall,the results of this study offer important theoretical parameters for the effective clinical use of five types of traditional Chinese medicines combined with lopinavir/ritonavir to reduce the occurrence of clinical adverse reactions.
RESUMO
ObjectiveTo demonstrate the project scope of the afferent nerves of the lumbar intervertebral disc,on which basis to explore the mechanism of the symptoms of discgenic low back pain.MethodsThirty Wistar rats were divided randomly into three groups of 10 rats each:the L4-5,L5-6,and L6 S1 group.Each group was further divided randomly into two subgroups,the experimental group and the control group,5 rats for each group.Intervertebral disc was exposed through the posterior approach under peritoneal cavity anesthesia,after the nerve roots were pull away,2 μl of 30％ cholera toxin-horseradish peroxidase (CT-HRP) was injected into the inner layer of the intervertebral disc in the experimental group,while 2 μl of 0.9％ Nacl was used in the control group.Forty-eight hours after the surgery,all rats were perfused and bilateral dorsal root ganglions(DRGs) of T10-L3 were resected and fixxied.Each DRG was sectioned at 30 μm thickness and processed by DAB method.The sections of DRGs were coverslipped and observed by optical microscopy for the neurons or axons labelled by CT-HRP.It was judged as positive that brownish-black particles were in the neurons or axons.ResultsNot in a single dorsal root ganglions,but in a scope of dorsal root ganglions axons labled by CT-HRP could be seen in the rats in the experimental groups.No CT-HRP labled neurons or axons were seen in dorsal root ganglions in the contral groups.ConclusionAfferent nerves of the lumbar intervertebral disc project to a scope of dorsal root ganglions,which is the anatomic basis of the mechanism of the symptoms of discgenic low back pain.