OBJECTIVETo examine the relaxant effects of hydro-ethanolic, macerated aqueous (MA) and lipidfree macerated aqueous (LFMA) extract of Tymus vulgaris on tracheal chains of guinea pigs.

METHODSThe relaxant effects of five cumulative concentrations of each extract (0.4, 0.8, 1.2, 1.6 and 2.0 g/100 mL) were compared with saline as negative control and five cumulative concentrations of theophylline (0.1, 0.2, 0.4, 0.6 and 0.8 mmol/L) on precontracted tracheal smooth muscle of guinea pig with 60 mmol/L KCl (group 1) and 10 µmol/L methacholine (group 2, n=6 for each group).

RESULTSIn group 1 all concentrations of theophylline, three higher concentrations of hydro-ethanolic, two concentrations of LFMA and last concentration of MA extracts showed significant relaxant effects compared with that of saline (P<0.05 or P<0.01). Two lower concentrations of LFMA and all concentrations of MA except higher one caused contraction compared with saline (P<0.05 or 0.01). In group 2 experiments, all concentrations of theophylline, hydro-ethanolic, MA and LFMA extracts showed significant relaxant effects compared to that of saline (P<0.05 or P<0.01). In both groups, the relaxant effect of all concentrations of hydro-ethanolic extract were significantly higher than most concentrations of others (P<0.05 or P<0.01). The relaxant effect of different concentrations of three extracts were significantly greater in group 2 compared with group 1 experiments (all P<0.01). There were significantly positive correlations between the relaxant effects and concentrations for theophylline and all extracts in both groups (P<0.05 or P<0.01).

CONCLUSIONHydro-ethanolic extract has a potent weaker relaxant effect for other extracts from Tymus vulgaris on tracheal chains of guinea pigs.

Animals ; Bronchodilator Agents ; pharmacology ; Guinea Pigs ; In Vitro Techniques ; Lamiaceae ; chemistry ; Lipids ; chemistry ; Muscle Relaxation ; drug effects ; Muscle, Smooth ; drug effects ; physiology ; Plant Extracts ; pharmacology ; Solubility ; Solutions ; Theophylline ; Trachea ; physiology ; Water ; chemistry

OBJECTIVETo investigate the effect of the anticoagulants on PRP quality, so as to clarify the appropriate anticoagulant used in PRP production.

METHODSThe microstructure change of platelets collected via heparin, citrate, acid citrate dextrose (ACD) and citrate-theophylline-adenosine-dipyridamole ( CTAD) was observed by TEM following time course. The extent of spontaneous activation of platelets in four groups was detected by measuring sP-selectin in plasma. The TGF-β1 release amount of activated PRP of four groups was measured.

RESULTSCTAD is superior to other anticoagulants in maintaining the integrity of platelet structures for a long time and preventing platelet spontaneous activation. ACD slightly surpassed heparin and citrate in above two aspects. ACD-PRP and CTAD-PRP released significantly more TGF-β1 compared with heparin and citrate.

CONCLUSIONSThe PRP quality and biological effects were strongly associated with the type of Anticoagulants. ACD and CTAD are optimal anticoagulants in PRP production for they can maintain platelet viability at a high level.

Adenosine ; pharmacology ; Anticoagulants ; pharmacology ; Blood Platelets ; drug effects ; physiology ; Citrates ; pharmacology ; Citric Acid ; pharmacology ; Dipyridamole ; pharmacology ; Drug Combinations ; Glucose ; analogs & derivatives ; pharmacology ; Heparin ; pharmacology ; Platelet Activation ; drug effects ; Platelet-Rich Plasma ; Theophylline ; pharmacology ; Transforming Growth Factor beta1 ; metabolism

To study the effect of Tibetan medicine Zuotai on the activity, protein and mRNA expression of CYP1A2 and NAT2, three different doses (1.2, 3.8 and 12 mg x kg(-1)) of Zuotai were administrated orally to rats once a day or once daily for twelve days, separately. Rats were administrated orally caffeine (CF) on the second day after Zuotai administration, and the urine concentration of CF metabolite 5-acetylamino-6-formylamino-3-methyl-uracil (AFMU), 1-methyluric acid (1U), 1-methylxanthine (1X), 1, 7-dimethylxanthine (17U) at 5 h after study drug administration was determined by RP-HPLC. The activity of CYP1A2 and NAT2 was evaluated by the ratio of metabolites (AFMU+1X+1U)/17U and the ratio of AFMU/(AFMU+1X+1U), respectively. The protein and mRNA expression of CYP1A2 and NAT2 were determined by ELISA and RT-PCR method, respectively. After single administration of Zuotai 3.8 mg x kg(-1) and repeated administration of Zuotai 3.8 and 12 mg x kg(-1), the activity of CYP1A2 and NAT2 decreased significantly compared with control group and there was no significant difference between other dose group and control group. The protein expression of CYP1A2 was significant lower than that in control group after repeated administration of Zuotai 12 mg x kg(-1), and the mRNA expression of CYP1A2 decreased significantly compared with that of control group after single administration of Zuotai 3.8 mg x kg(-1) and repeated admistration of Zuotai 12 mg x kg(-1), separately. The protein expression of NAT2 decreased significantly compared with that of control group after single and repeated administration of Zuotai 3.8 mg x kg(-1), respectively, and the mRNA expression of CYP1A2 decreased significantly compared with control group after single administration of Zuotai 3.8 mg x kg(-1). This study found that Tibetan medicine Zuotai had significant effect on the activity, protein and mRNA expression of CYP1A2 and NAT2.
Administration, Oral ; Animals ; Arylamine N-Acetyltransferase ; genetics ; metabolism ; Caffeine ; metabolism ; urine ; Cytochrome P-450 CYP1A2 ; genetics ; metabolism ; Dose-Response Relationship, Drug ; Drugs, Chinese Herbal ; administration & dosage ; pharmacology ; Female ; Male ; Medicine, Tibetan Traditional ; RNA, Messenger ; metabolism ; Rats ; Rats, Sprague-Dawley ; Theophylline ; urine ; Uracil ; analogs & derivatives ; urine ; Uric Acid ; analogs & derivatives ; urine ; Xanthines ; urine

OBJECTIVETo investigate the possible roles of adenosine and the cytokines TNF-alpha and IL-10 in the pathogenesis of acute bacterial prostatitis (ABP) in rats.

METHODSForty-eight male Wistar rats were randomly divided into groups A (ABP), B (ABP + theophylline intervention), C (sham) and D (blank control). ABP models were established by injecting Escherichia coli 0157 into the prostate, and those in group B were treated by intraperitoneal injection of theophylline immediately after modeling. At 4 and 14 days, the prostate tissues of the rats were collected for detection of the expressions of TNF-alpha and IL-10 by immunohistochemistry and the concentration of adenosine by high-performance liquid chromatography.

RESULTSAt 4 and 14 days, the concentrations of adenosine were significantly higher in group A ([48.38 +/- 17.27] and [26.54 +/- 11.22] microg/g) than in C ([0.45 +/- 0.25] and [0.46 +/- 0.29] microg/g) and D ([0.41 +/- 0.23] and [0.43 +/- 0.27] microg/g) (P < 0.05), and so were the expressions of TNF-alpha in A (0.23 +/- 0.08 and 0.21 +/- 0.03) than in C (0.07 +/- 0.03 and 0.07 +/- 0.01) and D (0.07 +/- 0.06 and 0.07 +/- 0.06) (P < 0.05), and those of IL-10 in A (0.13 +/- 0.03 and 0.25 +/- 0.01) than in C (0.07 +/- 0.03 and 0.07 +/- 0.03) and D (0.07 +/- 0.01 and 0.07 +/- 0.02) (P < 0.05). Compared with group A, the rats in group B showed significant increases at 4 and 14 days in the severity of inflammation, concentration of adenosine ([86.64 +/- 32.87] and [51.17 +/- 22.96] microg/g, P < 0.05) and expression of TNF-alpha (0.37 +/- 0.08 and 0.32 +/- 0.06, P < 0.05), but exhibited no remarkable difference in the expression of IL-10 (0.12 +/- 0.06 and 0.15 +/- 0.06, P > 0.05).

CONCLUSIONAdenosine may affect the progression of inflammation by regulating the expressions of the cytokines TNF-alpha and IL-10 in ABP rats through the adenosine receptor signaling pathway.

Adenosine ; physiology ; Animals ; Escherichia coli O157 ; Interleukin-10 ; metabolism ; Male ; Prostate ; drug effects ; metabolism ; Prostatitis ; metabolism ; microbiology ; Random Allocation ; Rats ; Rats, Wistar ; Theophylline ; pharmacology ; Tumor Necrosis Factor-alpha ; metabolism

OBJECTIVETo compare the effect of Acanthopanacis senticosi injection, theophylline and caffeine on human sperm mobility in vitro.

METHODSWe incubated the sperm aseptically obtained by masturbation from 12 asthenospermia men and treated by swim-up technique in Acanthopanacis senticosi injection (10 g/L), theophylline (3 mmol/L) and caffeine (7 mmol/L) respectively, and detected various sperm parameters with the computer-assisted sperm analysis (CASA) system at 0 h, 1 h and 3 h.

RESULTSAcanthopanacis senticosi injection significantly increased sperm motility, the percentage of progressive motile sperm, straight line velocity (VSL) and curvilinear velocity (VCL) as compared with theophylline and caffeine (P < 0.05).

CONCLUSIONAcanthopanacis senticosi injection can activate the mobility of human sperm in vitro.

Caffeine ; pharmacology ; Drugs, Chinese Herbal ; pharmacology ; Eleutherococcus ; chemistry ; Humans ; In Vitro Techniques ; Male ; Sperm Motility ; drug effects ; Theophylline ; pharmacology

Administration, Inhalation ; Adrenal Cortex Hormones ; pharmacology ; Asthma ; drug therapy ; metabolism ; Child ; Child, Preschool ; Drug Interactions ; Drug-Related Side Effects and Adverse Reactions ; Female ; Humans ; Male ; Theophylline ; pharmacokinetics ; pharmacology ; Treatment Outcome

High level of adenosine A1 receptor-like immunoreactivity has been found in the CA2/CA3a region of adult rat hippocampus, but its roles in the neuronal activity or signal propagation in hippocampus and its intracellular cascade remain to be studied. In this study, we examined the relation between adenosine-3',5'-cyclic monophosphate (cAMP) cascade and suppression of synaptic transmission by endogenous adenosine through adenosine A1 receptor in the CA2 area. In transverse hippocampal slice, maximal electrical stimulation of the hilus region (0.6 mA) only evoked small population spikes (PSs) in the CA2 area (0.5 mV). In the presence of forskolin (20 micromol/L), a direct adenylate cyclase activator, PSs in CA2 were increased to 1.1 mV. When 8-cyclopentyltheophylline (8CPT, 2 micromol/L), an adenosine A1 receptor antagonist, was added in the presence of 20 micromol/L forskolin, PSs with an average amplitude of 4.7 mV were recorded in the CA2 area, much higher than the sum of the amplitude of PSs in the presence of forskolin and 8CPT alone. To test whether this synergistic potentiation results from the additive activation of cAMP cascade, the cAMP content in hippocampal slices was measured with enzyme immunoassay (EIA). Results showed that 8CPT did not increase the cAMP content in CA2 with or without forskolin. Co-application of forskolin and Ro 20-1724, a cAMP-specific phosphodiesterase-IV inhibitor, only increased PSs in CA2 to 1.3 mV but increased cAMP content by 4.4 times. On the other hand, co-application of 8CPT and 1, 9-dideoxyforskolin, a forskolin analog which has no effect on adenylate cyclase, did not mimic the synergistic effect of 8CPT and forskolin on PSs in CA2. These results indicate that up-regulation of adenylate cyclase activity and inhibition of adenosine A1 receptor activity synergistically facilitate the neuronal activity in the CA2 area and the effect of adenosine A1 receptor antagonist is via non-cAMP cascade. These data also suggest that acting on adenosine A1 receptors, endogenous and extragenous adenosine/adenosine A1 agonist(s) inhibit neuronal activity through different pathways.
Adenosine A1 Receptor Antagonists ; Adenylyl Cyclases ; metabolism ; Animals ; Colforsin ; pharmacology ; Cyclic AMP ; physiology ; Drug Synergism ; Hippocampus ; drug effects ; physiology ; Long-Term Potentiation ; drug effects ; Male ; Neurons ; drug effects ; physiology ; Rats ; Rats, Wistar ; Theophylline ; analogs & derivatives ; pharmacology

OBJECTIVETo investigate the feasibility and benefits of co-culture of cryopreserved islets with small intestinal submucosa (SIS).

METHODSPurified rat islets cryopreserved for one month were divided into SIS group and control group, and after culture in standard islet culture media RPMI1640 for 1 week, the morphology and function of the islets were assessed.

RESULTSThe SIS protects the fragile islets from damage by cryopreservation, and increased the recovery from (60.6-/+3.3)% to (91.7-/+1.8) % (P<0.05). Compared with the control group, incubation of the islets of the SIS group in high-glucose (16.7 mmol/L) solution resulted in significantly enhanced insulin secretion (23.7-/+1.6 vs 12.5-/+1.1 mU/L, P<0.05). When the islets were incubated in high-glucose solution containing theophylline, the calculated stimulation index of SIS group was about 3-fold higher than that of the control group.

CONCLUSIONCo-culture of cryopreserved rat islets with SIS can increase the recovery of islet cells and improve their function.

Animals ; Coculture Techniques ; Cryopreservation ; methods ; Glucose ; pharmacology ; Insulin ; secretion ; Intestinal Mucosa ; cytology ; drug effects ; physiology ; Intestine, Small ; cytology ; drug effects ; physiology ; Islets of Langerhans ; cytology ; drug effects ; physiology ; Male ; Rats ; Rats, Wistar ; Theophylline ; pharmacology

Drug-drug interaction (DDI) is defined as a change in effect or safety of a drug by another co-administered drug. The fact that more than half of the market withdrawal cases for the past ten years was caused by potentially fatal DDI's demonstrates its clinical importance. The mechanism of DDI can be categorized into pharmacokinetic and pharmacodynamic interactions. Most of the clinically important drug interactions are caused by inhibition or induction of oxidative metabolism by cytochrome P450 (CYP) isozymes. Recent researches are also focusing on drug transporter interactions as another significant factor underlying DDI's. It is hard to prevent unexpected or rare DDI's. However, most of the cases of DDI occur from an erroneous prescription of drugs that are already known to result in deleterious interactions. To avoid such well-established DDI's, physicians are first recommended to utilize hands-on summary tables for CYP substrates before prescribing. It should also be remembered that old age, polypharmacy and damaged hepatic or renal function are risk factors of DDI as well as adverse drug reactions. Moreover, patients treated with drugs with a narrow therapeutic index (immunosuppressants, antiarrhythmics, anticoagulants, digoxin, theophylline etc) deserve a special consideration when their prescriptions are changed. In Korea, the clinical significance of DDI has been underemphasized. The fundamental prescription to this old prescription habit is to teach medical students and physicians clinical pharmacology and therapeutics, which have long been neglected in Korea.
Anticoagulants ; Cytochrome P-450 Enzyme System ; Digoxin ; Drug Interactions ; Drug-Related Side Effects and Adverse Reactions ; Humans ; Isoenzymes ; Korea ; Metabolism ; Pharmacology, Clinical ; Polypharmacy ; Prescriptions ; Product Recalls and Withdrawals ; Risk Factors ; Students, Medical ; Theophylline

AIMTo identify the cytochrome P450 (CYP) isoform (s) involved in daidzein mono-hydroxylated metabolites using human liver microsomes.

METHODSKinetic analysis of the rates of formation of mono-hydroxylated metabolites of daidzein, including 7,8,4'-trihydroxyisoflavone (7,8,4'-THI), 7,3',4'-trihydroxyisoflavone (7,3',4'-THI) and 6,7,4'-trihydroxyisoflavone (6,7,4'-THI), was performed using human liver microsomes (HLM) and recombinant enzymes at substrate concentrations ranging from 0.5 to 400 micromol x L(-1). Nine selective inhibitors or substrate probes specific for different CYP isoforms were applied for screening the isoform(s) responsible for mono-hydroxylated metabolism of daidzein.

RESULTSMichaelis-Menten kinetic parameters were best fitted to one-component enzyme kinetic model. The mean Km (micromol x L(-1) ) and V(max) (micromol x g(-1) x min(-1)) values were 27 +/- 10 and 4. 8 +/- 2.1, 54 +/- 22 and 2.3 +/- 1.0, 51 +/- 29 and 2.2 +/- 0.8, for the formation rates of 7,8,4'-THI, 7,3',4'-THI, and 6,7,4'-THI, respectively. Furafylline, the CYP1A2 specific inhibitor, estrogen, and monoclonal antibody raised against human CYP1A2 (MAB-1A2) apparently inhibited the formation of mono-hydroxylated metabolites, The IC50 of Fur for the formation of 7,3',4'-THI, 6,7,4'-THI and 7,8,4'-THI was 1.0, 0.9 and 0. 8 mol x L(-1), respectively. The IC50 of estrogen for the formation of 7,3',4'-THI, 6,7,4'-THI and 7,8,4'-THI were 51, 60 and 64 mol x L(-1) respectively. The IC50 of MAB-1A2 for the formation of the mono-hydroxylated products was 1 mol x L(-1), but neither other selective inhibitor nor substrate probes, including coumarin (CYP2D6), sulphaphenzole ( CYP2C9/10), omeprazole ( CYP2C19), quinidine (CYP2D6), diethyldithiocarbamate (CYP2E1), troleandomycin (CYP3A4) and keteconazole (CYP3A4), did so with human liver microsomes.

CONCLUSIONThe in vitro studies indicated that daidzein mono-hydroxylated products were principally metabolized by CYP1A2 in human.

Cytochrome P-450 CYP1A2 ; metabolism ; Cytochrome P-450 CYP1A2 Inhibitors ; Estrogens ; pharmacology ; Humans ; Hydroxylation ; Isoflavones ; metabolism ; Microsomes, Liver ; metabolism ; Theophylline ; analogs & derivatives ; pharmacology