Study on the effect of spinal anesthesia on ventricular arrhythmias in acute myocardial ischemia-reperfusion in rats / 中国临床药理学与治疗学

AIM: To explore the effect of spinal anesthesia on ventricular arrhythmia and involved mechanisms in myocardial ischemia-reperfusion (MIR) rats. METHODS: The rat MIR model was made by occlusion the left anterior descending coronary artery for 30 minutes and reperfusion for 45 minutes. Bupivacaine (0.05 mL / 100 g, 1 mg / kg) was injected slowly via intrathecal for spinal anesthesia. The electromyelogram at T2 thoracic spinal cord was recorded. Ventricular arrhythmias, cardiac function, myocardial damage were assessed by electrocardiography, echocardiography and TTC or HE staining. RESULTS: MIR reduced left ventricular short-axis shortening (LVFS) and left ventricular ejection fraction (LVEF), caused myocardial histological damage and ventricular arrhythmias, promoted spinal electrical discharge frequency and amplitude in T2 dorsal horn. Spinal injection of bupivacaine could significantly reduce spinal cord electrical activities and eliminate MIR-induced arrhythmias. Moreover, bupivacaine also significantly improved MIR-induced myocardial histological damage and cardiac function inhibition. CONCLUSION: Spinal anesthesia can reduce ventricular arrhythmias induced by MIR. The mechanism may be related to the effect of abolishing spinal nerve excitability.

Pharmacokinetics of tramadol hydrochloride in the extracellular fluid of mouse frontal cortex studied by in vivo microdialysis / 药学学报

The paper aims to explore the studying method for the pharmacokinetics of drugs in target organs, the pharmacokinetic process of tramadol hydrochloride in the extracellular fluid of frontal cortex (FrCx) of mice was investigated. Six male mice (Kunming strain) were anaesthetized (urethane, 1.8 g x kg(-1), ip) and secured on a stereotaxic frame. A microdialysis probe was implanted into the FrCx and perfused with artificial cerebrospinal fluid at a flow rate of 2 microL x min(-1). One hour later, mice were administrated (ip) with tramadol hydrochloride (50 mg x kg(-1)) and dialysates were collected continuously at 12-min intervals (24 microL each) for 6 h. The tramadol concentration in dialysates was determined by HPLC-Ultraviolet detection method, and the concentration-time curve and pharmacokinetic parameters of tramadol were calculated with DAS software. The results showed that the pharmacokinetic process of tramadol in the FrCx extracellular fluid of mice was fitted to a two-compartment open model, and the main pharmacokinetic parameters t1/2alpha, t1/2beta, t(max), C(max) and AUC(0-infinity) were (0.27 +/- 0.05) h, (2.72 +/- 0.24) h, (0.50 +/- 0.10) h, (2 110.37 +/- 291.22) microg x L(-1) and (4 474.51 +/- 441.79) microg x L(-1) x h, respectively. In conclusion, a studying method for pharmacokinetics of drugs in the target organ is established, which is simple and feasible. Tramadol hydrochloride shows a two-compartment model in the extracellular fluid of the mouse FrCx, and the distribution- and elimination half-life are 0.5 h and 2.7 h, respectively.

Peoniflorin activates Nrf2/ARE pathway to alleviate the Abeta(1-42)-induced hippocampal neuron injury in rats / 药学学报

This study was to investigate the effect of peoniflorin on the expressions of nuclear factor erythroid 2-related factor 2 (Nrf2) and its downstream signal molecules in the hippocampus of Alzheimer's disease (AD) rats for exploring the mechanism of peoniflorin protecting hippocampal neurons. AD model rats were established by bilateral intrahippocampal injection of beta-amyloid(1-42) (Abeta(1-42)) and divided randomly into 3 groups: AD model group, peoniflorin low-dose (15 mg x kg(-1)) group and peoniflorin high-dose (30 mg x kg(-1)) group. The vehicle control rats were given bilateral intrahippocampal injection of solvent with the same volume. After peoniflorin or saline was administered (ip) once daily for 14 days, the hippocampuses of all animals were taken out for measuring the expressions of Nrf2, heme oxygenase-1 (HO-1) and gamma-glutamylcysteine synthethase (gamma-GCS) mRNA by reverse transcription PCR, determining the contents of glutathione (GSH), malondialdehyde (MDA) and carbonyl protein (CP) using colorimetric method, and for assaying the expressions of neuronal apoptosis inhibitory protein (NAIP) and Caspase-3 by immunohistochemical staining method. The results showed that peoniflorin markedly increased the expressions of Nrf2, HO-1 and gamma-GCS mRNA, enhanced the level of GSH and decreased the contents of MDA and CP in the hippocampus, as compared with the model group. Peoniflorin also improved the NAIP expression and reduced the Caspase-3 expression in the hippocampus neurons. In conclusion, peoniflorin protects against the Abeta(1-42)-mediated oxidative stress and hippocampal neuron injury in AD rats by activating the Nrf2/ARE pathway.

Pharmacokinetics--pharmacodynamics of modafinil in mice / 药学学报

To guide the reasonable clinical application of modafinil (MOD), pharmacokinetics and pharmacodynamics of MOD in mice and the correlation between them were investigated. Male mice (Kunming strain) were given a single oral dose of MOD (120 mg x kg(-1)). The plasma concentration of MOD was measured by HPLC and the pharmacokinetic parameters were calculated with DAS 3.0 software. For another batch of male Kunming strain mice, their locomotor activities were recorded by an infrared ray passive sensor after a same oral dose of MOD, and the synchronization and correlation between the changes of MOD plasma concentration and the locomotor activity induced by MOD were compared and analyzed. The results showed that the plasma concentration-time curve of MOD was fitted to two-compartment open model with a first order absorption. The main pharmacokinetic parameters t1/2alpha, t1/2beta, t(max), C(max) and AUC(0-inifinity) were 0.42 h, 3.10 h, 1.00 h, 41.34 mg x L(-1) and 142.22 mg x L(-1) x h, respectively. MOD significantly increased locomotor activity and the effect lasted for about 4 h. The changes of MOD plasma concentration and the locomotor activity induced by MOD were synchronous. In conclusion, there is a significant correlation between the effect of MOD and its plasma concentration after administration of 120 mg x kg(-1) in mice.

Anti-inflammation effect of danggui shaoyao san on Alzheimer's diseases / 中国中药杂志

<p><b>OBJECTIVE</b>To study the mechanisms of Danggui Shaoyao San (DSS) on Alzheimer's diseases (AD) focusing on anti-inflammation.</p><p><b>METHOD</b>AD rats were established by intrahippocampal bilateral injection of Abeta1-42 protein. The AD rats were randomly divided into three groups: AD model group, DSS high-dose group, DSS low-dose group. Vehicle group rats were intrahippocampal bilateral injection of solvent with the same dose. The learning ability and memory of rats was investigated in step-down passive avoidance test and Morris water maze test, expression of IL-1beta, IL-6, TNF-alpha mRNA were observed by reverse transcriptase PCR (RT-PCR), levels of NO was measured by colorimetric method and neuron apoptosis in the hippocampus was investigated by tag method of TdT-mediated end-labeling of fragmented DNA (TUNEL).</p><p><b>RESULT</b>DSS significantly reduced the escape latency and increased the time that rats spent in the target quadrant in Morris water maze test, shortened the responsive latency and decreased the error numbers in step-down passive avoidance test, reduced the expression of the IL-1beta, IL-6, TNF-alpha mRNA, and the level of the NO depressed the neuron apoptosis in the hippocampus.</p><p><b>CONCLUSION</b>DSS improving cognition of the rats might be related to attenuate inflammatory reaction and reduce cell apoptosis in the hippocampus.</p>

Tissue distribution in mice of danshensu from sodium danshensu and Salvia miltiorrhiza injection / 中国中药杂志

<p><b>OBJECTIVE</b>To determine the concentration in mice of danshensu from sodium danshensu and Salvia miltiorrhiza injection and undertake comparative study of them as well as to assess the effect of other components of S. miltiorrhiza injection on the tissue distribution of danshensu.</p><p><b>METHOD</b>Mice received intraperitoneal administration of sodium danshensu or S. miltiorrhiza injection (equal to danshensu 60 mg x kg(-1)) respectively, and was executed 30 minutes after administration. The concentration of danshensu in different tissues was separately determined by high performance liquid chromatographic method.</p><p><b>RESULT</b>The characteristic profiles of sodium danshensu in different tissues were C(kidney) > C(spleen) > C(lung) > C(heart) > C(liver). The characteristic profiles of danshensu from S. miltiorrhiza injection in different tissues were C(kidney) > C(lung) > C(spleen) > C(heart) approximately C(liver). The concentration of danshensu in S. miltiorrhiza injection in liver and kindey was higher than sodium danshensu itself.</p><p><b>CONCLUSION</b>It was suggested that the other components in S. miltiorrhiza injection influent the distribution profile in tissues of danshensu.</p>

Advances in the study of histaminergic systems and sleep-wake regulation / 药学学报

Histaminergic neurons solely originate from the tuberomammillary nucleus (TMN) in the posterior hypothalamus and send widespread projections to the whole brain. Experiments in rats show that histamine release in the central nervous system is positively correlated with wakefulness and the histamine released is 4 times higher during wake episodes than during sleep episodes. Endogeneous prostaglandin E2 and orexin activate histaminergic neurons in the TMN to release histamine and promote wakefulness. Conversely, prostaglandin D2 and adenosine inhibit histamine release by increasing GABA release in the TMN to induce sleep. This paper reviews the effects and mechanisms of action of the histaminergic system on sleep-wake regulation, and briefly discusses the possibility of developing novel sedative-hypnotics and wakefulness-promoting drugs related to the histaminergic system.

Comparative pharmacokinetic study of sodium Danshensu and Salvia miltiorrhiza injection in rat / 中国中药杂志

<p><b>OBJECTIVE</b>To develop a HPLC method for determination of the concentration of Danshensu in rat plasma and undertake comparative pharmacokinetic study of sodium danshensu and Salvia miltiorrhiza injection in rat as well as to assess the effect of other components of Salvia miltiorrhiza injection on the pharmacokinetics of Danshensu.</p><p><b>METHOD</b>Rats received an iv. infusion of sodium Danshensu or S. miltiorrhiza injection (equal to Danshensu 30 mg x kg(-1)). Blood samples were collected from carotid artery. Plasma concentration of Danshensu extracted with perchloric acid was measured. The pharmacokinetic parameters were calculated with DAS2.0 software.</p><p><b>RESULT</b>A good linear relationship of Danshensu was obtained from the range of 0.5 to 80.0 mg x L(-1), and the lowest limit of determination was 0.2 mg x L(-1). The plasma concentration time curves of Danshensu were best fitted with two-compartment models for Danshensu itself and for Salvia miltiorrhiza injection as well. The pharmacokinetic parameters such as t1/2alpha, AUC, CL had significant differences.</p><p><b>CONCLUSION</b>The concomitant components in Salvia miltiorrhiza injection influence the pharmacokinetic properties of Danshensu and speed up its disposition and elimination.</p>

Characteristics of sleep-wake cycles in mice lacking prostanoid DP receptors / 中国临床药理学与治疗学

AIM: To investigate the effect of prostanoid DP receptors (DPR) on sleep-wake regulation in mice. METHODS: Under pentobarbital anesthesia, mice were chronically implanted with electroencephalogram (EEG) and electromyogram (EMG) electrodes for polysomnographic recordings. The spontaneous sleep-wake cycles were monitored continuously by EEG/EMG recording system for 24 h beginning at 800 p.m. and analyzed by SLEEPSIGN software in DPR knock out (KO) and wild type (WT) mice. RESULTS: DPR-KO mice exhibited a similar circadian rhythm of sleep-wake cycles to WT mice. The amounts of rapid eye movement (REM) sleep or non-REM (NREM) sleep during both the light and dark periods were identical between the DPR-KO and WT mice. Whereas, an increase in the episode number of wakefulness and a shortage in the duration of NREM sleep were found in DPR-KO mice during the light period compared with WT mice. Moreover, DPR-KO mice showed lower activity in delta-wave component in NREM sleep and higher activity in theta-wave component in REM sleep than WT mice. CONCLUSION: DPR plays a crucial role in mediating the prostaglandin D2-induced sleep. Deficiency of DPR results in the low intensity and fragmented diurnal NREM sleep and the high vigilance REM sleep, with the normal circadian rhythm of sleep in mice.

Effect of prostaglandin D_2 on sleep regulation / 中国临床药理学与治疗学

Prostaglandin (PG) D_2 is one of unsaturated fatty acids with 20 carbon atoms, which is synthesized by PGD synthase (PGDS) in the brain. PGD_2 has been identified to be a sleep-inducing substance that becomes bound to the DP receptor (DPR) exclusively localized on the surface of the basal forebrain, leading to an increase in extracellular adenosine levels there. Through A_ 2A receptors (A_ 2A R), the adenosine activates neurons in the ventrolateral preoptic area (VLPO), a putative sleep center, and inhibits neurons in the histaminergic tuberomammillary nucleus (TMN), a putative wake center, via GABA to induce sleep. Studying the effect and the molecular mechanisms of sleep-induced by PGD_2 would be helpful in the development of novel sleeping drugs for more rational treatment of sleep disorders.

Therapeutic effect of tea polyphenols on cationic bovine serum albumin glomerulonephritis in rabbits / 中国临床药理学与治疗学

AIM: To investigate the therapeutic effect of tea polyphenols (TP) on cationic bovine serum albumin (C BSA) glomerulonephritis. METHODS: C BSA glomerulonephritic model was induced in rabbits. TP in three different doses (30, 100 and 300 mg?kg -1 ) was administered (ig) once daily for 14 days. RESULTS: TP not only significantly reduced the urinary protein excretion, decreased blood urea nitrogen (BUN) and plasma creatinine (Cr) levels, but also significantly relieved gloermular lesions in the rabbits treated and there was a significant dose dependent relationship between high dosage (300 mg?kg -1 ) and low dosage ( 30 mg?kg -1 ). CONCLUSION: TP can reduce proteinuria, suppress the development of glomerular impairments, and ameliorate the kidney function of rabbits with C BSA glomerulonephritis.