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AIM:To study the effects of noninvasive delayed limb ischemia preconditioning ( NDLIP) on ani-mal cardiac function , myocardial morphology and myocardial apoptosis after myocardial infarction ( MI ) .METHODS:Healthy SD male rats [n=45, weighing (250 ±10) g] were randomly divided into 3 groups:MI group:the animal model of MI was established by surgical ligation of left anterior descending artery ( LAD) after 2 weeks;NDLIP group:after the success of the MI animal model , NDLIP was carried out every other day until the 4th, 6th and 8th weeks;sham group:as the negative control group , the animals were taken heart LAD threading but no ligation .All rats were fed conventionally .At the end of the 4th, 6th and 8th weeks, all rats were made ventricular intubation , and then the hemodynamic parameters were recorded .The blood samples were withdrawn from the abdominal aorta and the serum was separated via centrifugation . The serum contents of Bcl-2 and Bax were measured by ELISA .Left ventricular anterior wall was homogenized .The mito-chondrial respiratory chain complexes Ⅰ,Ⅱ,Ⅲand Ⅳin the myocardial tissues were detected by ELISA .RESULTS:At the end of the 4th, 6th and 8th weeks, compared with MI group, left ventricular systolic pressure in NDLIP group was significantly increased , while left ventricular end-diastolic pressure in NDLIP group was significantly decreased ( both P<0.05).Mitochondrial respiratory chain complexesⅠ, Ⅱ, Ⅲ and Ⅳ in NDLIP group were significantly increased (P<0.05).The serum level of Bcl-2 in NDLIP group was significantly increased and Bax level was reduced remarkably (both P<0.01) .CONCLUSION:NDLIP improves the hemodynamic indexes , promotes the mitochondrial respiratory function and inhibits cell apoptosis , thus improving the prognosis of MI .
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Aim To investigate the protective effects of sphingosine 1-phosphate ( S1 P ) postconditioning on hypoxia/reoxygenation( H/R) injury in human umbili-cal vein endothelial cells ( HUVEC ) and its mecha-nisms. Methods HUVECs cells were divided into five groups: normal ( control) group, S1P low concentra-tion group ( L ) , S1 P medium concentration group (M), S1P high concentration group ( H) and H/R group. MTT method was used to measure cell survival. Using flow cytometric analysis, the rate of cell apopto-sis was determined. The activities of total superoxide dismutase ( T-SOD) , copper/zinc superoxide dismuta-se ( CuZn-SOD ) , manganese superoxide dismutase ( Mn-SOD) activity, nitric oxide ( NO) and malondial-dehyde ( MDA ) content in cell culture medium were measured with colorimetry. Mitochondrial membrane potential in cells was observed with fluorescence micro-scope. Bax/Bcl-2, eNOS protein expression levels in HUVECs cells were observed with Western blot. Re-sults Compared with H/R group, S1P low, medium and high concentrations in the intervention group could significantly increase the cell survival rate after H/R injury, and increase activity of T-SOD, CuZn-SOD, Mn-SOD and decrease content of MDA. Moreover, S1 P could significantly increase NO content and in-crease eNOS protein expression, decrease apoptosis rate and inhibit the reduction of mitochondrial mem-brane potential. Conclusions S1P can decrease cell apoptosis rate of HUVECs after H/R injury with a cer-tain concentration dependence. The protection of S1P for cell apoptosis of HUVECs after H/R injury may be related to decreasing the intracellular MDA content and improving intracellular SOD activity, increasing mito-chondrial membrane potential and enhancing expres-sion of Bcl-2, anti-apoptotic protein.
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Aim To study the preventative effects of noninvasive delayed limb ischemic preconditioning ( NDLIP) on sudden cardiac death in rats with myocar-dial infarction. Methods Thirty healthy SD male rats weighting ( 250 ± 10 ) g were randomly divided into 3 groups:① myocardial infarction ( MI ) group: animal model of MI was established by making surgical ligation of animal LAD. ② MI plus NDLIP group: after the success of the animal model of MI, NDLIP was carried out every other day until 4th week. ③Sham group:as the negative control group, animals were taken heart LAD threading but no ligation. All rats were fed con-ventionally. At the end of 4 weeks, three groups of rats were administered with metaraminol ( 0. 2 mg · min-1 ) . ECG, drug cumulant of sudden death and death onset time were recorded. After sudden death, blood samples were withdrawn from abdominal aorta and serum was separated via centrifugation. ELISA method was used to measure serum caspase-3 , HSP70 and SOD concentration. Results While metaraminol led animal cardiac sudden death, the rats heart rate ( HR) kept declining with the increase of dosage of metaraminol during the administration period. Rat HR of MI+NDLIP group [ ( 479 ± 8 ) vs ( 416 ± 19 ) beat ·min-1 , ( 446 ± 32 ) vs ( 370 ± 20 ) beat · min-1 , (376 ± 53) vs (305 ± 29) beat·min-1, (307 ± 63) vs (244 ± 33) beat·min-1, (283 ± 45) vs (121 ± 35 ) beat · min-1 , P <0. 01 ] was markedly higher than that of MI group at 0 , 5 , 10 , 30 , 50 min before death. Compared with MI group, drugs cumulant to sudden death and death onset time of MI + NDLIP group [ ( 14. 58 ± 3. 03 ) vs ( 10. 76 ± 2. 73 ) mg, (72. 9 ± 15. 2 ) vs ( 53. 8 ± 13. 6 ) min, P <0. 01 ] were significantly increased. Compared with MI group, serum caspase-3 content of MI+NDLIP group was sig-nificantly reduced [ ( 2. 01 ± 0. 52 ) vs ( 2. 34 ± 0. 38 )μg·L-1 , P<0. 01 ]; HSP70 levels were remarkably increased [ ( 3. 01 ± 0. 58 ) vs ( 2. 70 ± 0. 43 ) μg · L-1 , P <0. 05 ]; SOD levels were significantly im-proved [(1. 99 ± 0. 65) vs (1. 70 ± 0. 58) mg·L-1, P<0. 01 ] . Conclusion NDLIP can prevent sudden cardiac death after myocardial infarction in rats, which may be mediated by reducing the myocardial cell apop-tosis, increasing protective protein expression and en-hancing antioxidant capacity.
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Aim To investigate the effects of dioscin ( Dio) on rat myocardial contractility. Methods Left ventricular contractile function was measured using the Langendorff non-recirculating mode of isolated rat heart perfusion. Effects of low, middle and high concentra-tion of Dio were investigated by measuring left ventricu-lar systolic pressure ( LVSP ) and left ventricular end diastolic pressure ( LVEDP) . Also, peak rates of rise/fall of left ventricular pressure ( ± dp/dtmax ) of isolated rat heart were calculated. Effects of Dio on intracellu-lar free calcium concentration in rat H9 c2 cells were measured by using the confocal microscopy. Mitochon-drial membrane potential was detected with multifunc-tional microplate reader. Results With 0. 1, 1 μmol · L-1 Dio, LVSP were significantly enhanced from (11. 55 ± 0. 52), (10. 53 ± 0. 28) kPa to (13. 08 ± 0. 72), (12. 53 ±0. 64) kPa(P<0. 01); +dp/dtmax were dramatically increased from ( 0. 38 ± 0. 10 ) , (0. 40 ± 0. 07) kPa·ms-1 to (0. 42 ± 0. 11), (0. 43 ± 0. 02) kPa·ms-1(P<0. 05). With the 10μmol· L-1 Dio, LVSP and + dp/dtmax were both decreased from (12. 13 ± 0. 33) kPa and (0. 42 ± 0. 04) kPa· ms-1 to ( 9. 46 ± 0. 77 ) kPa and ( 0. 24 ± 0. 04 ) kPa ·ms-1 (P <0. 01). With 0. 1, 1, 10 μmol·L-1 Dio, the relative fluorescence intensity of intracellular free calcium concentrations was increased significantly from (16. 62 ± 0. 89) to (21. 48 ± 0. 80), (25. 68 ± 0. 69) and (19. 84 ± 0. 66)(P <0. 01)respectively. 0. 1, 1μmol·L-1 Dio showed no significant effects on the mitochondrial membrane potential of rat H9 c2 cells, while with effects of 10 μmol·L-1 Dio, the ra-tio of JC-1 monomer and J-aggregates was changed from (1. 14 ± 0. 03) to (1. 35 ± 0. 06)(P<0. 01), indica-ting a decrease in the mitochondrial membrane poten-tial. Conclusion Low and middle concentrations of Dio show a positive inotropic effect on isolated rat heart, as the LVSP and + dp/dtmax are enhanced, which may concern with the increase of the intracellu-lar concentration of Ca2+. It will not cause the calcium overload while the intracellular concentration of Ca2+ is increased by low and middle concentration of Dio in the myocytes except high concentration of Dio.
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Objective To knock out Asxl2 gene in murine embryonic fibroblast cell line NIH3T3 using CRISPR/Cas9n system. Methods A pair of sgRNAs which targeted exon 5 of Asxl2 gene were designed and subcloned into the pX462 vec?tor. The recombined plasmids were verified by sequencing and transfected into NIH3T3 cell line. Single cells were isolated through serial dilutions, followed by an expansion period to obtain new monoclonal cell lines. The genomic DNA of the new monoclonal cell lines was extracted and a DNA fragment flanked the target site was amplified by genotyping PCR then se?quenced. Lastly, western blotting were applied to confirm whether Asxl2 was successfully knocked out. Results The CRIS?PR/Cas9n plasmids that targeted Asxl2 were successfully constructed. NIH3T3 cells were co-transfected with the two recom?binant constructs. After puromycin selection, subclonal cell lines were obtained and one of them was validated by genotyping PCR-sequencing. Western blotting also confirmed that Asxl2 was completely depleted in the NIH3T3 cell line. Conclu?sion CRISPR/Cas9n plasmids that targeted Asxl2 were successfully constructed therefore a Asxl2 knockout NIH3T3 stable cell line was established via this system.
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Aim To study the protective effects of sphingosine 1-phosphate (S1P) postconditioning on rat myocardial cells injured by hypoxia/reoxygenation in reperfusion injury salvage kinase ( RISK ) signal path-way. Methods The cultured rat H9c2 cells were ran-domly divided into seven groups: ( 1 ) control group;(2) hypoxia/reoxygenation (H/R) group; (3) S1P group;(4) S1P+LY294002 group(S1P+LY); (5) LY group; ( 6 ) S1 P +PD98059 group ( S1 P +PD );(7) PD group. The viability of H9c2 cells was detec-ted using MTT method. The content of MDA in the cultured medium and the activity of T-SOD and Mn-SOD were measured with colorimetry. The concentra-tion of intracellular free calcium ion was detected by confocal microscopy. The rate of cell apoptosis was de-termined by flow cytometric analysis. Western blot was used to assess phosphorylation of Akt and ERK1/2 in H9c2 cells. Results Compared with the H/R group, S1P significantly increased vaibility of cells, lowered the rate of apoptosis, decreased the content of MDA in the culture medium, increased the activity of T-SOD and Mn-SOD, reduced concentration of intracellular calcium and increased the phosphorylation of Akt and ERK1/2 . When added LY294002 or PD98059 , the effects of S1P above were inhibited. Conclusion S1P protects H9 c2 cells against hypoxia/reoxygenation inju-ry. The protection of S1P was inhibited by LY294002, the inhibitor of PI3 K/Akt and PD98059 , the inhibitor of ERK1/2 . S1 P protects H9 c2 cells against hypoxia/reoxygenation injury via RISK pathway.
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OBJECTIVE:To study the inhibitory effect of dihydrotanshinone(DTS)on human lung cancer GLC-82 cell and its mechanism. METHODS:After treated with 0(blank control),5,10,20,40,80 and 100 μg/ml DTS for 24 and 48 h,MTT as-say was used to measure the inhibition rates and IC50 of cells;cell apoptosis was detected by flow cytometry after treated with 17.85 μg/ml DTS for 12,24 and 48 h to calculate apoptotic rate;Western blot was used to detect the protein expressions of Bcl-2, Bax and Caspase-3. RESULTS:Compared with blank control group,different concentrations of DTS inhibited the proliferation of cells;24 and 48 h maximal inhibition rate were 54.48% and 64.95%,respectively;IC50 were 62.36 and 33.94 μg/ml. DTS could induce cell apoptosis in positive time dependent manner,and the range of inhibition rate was 5.6%-29.6%;Western blot showed DTS could down-regulate the expression of Bcl-2 protein and up-regulate the expression of Caspase-3 protein (P<0.01 or P<0.05). CONCLUSIONS:DTS have significant inhibitory effect on GLC-82 cells and also induce cell apoptosis,by a possible mech-anism of down-regulating the expression of Bcl-2 protein and up-regulating the expression of Caspase-3 protein.
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Aim To investigate the effects of TMCC on abnormal L-type calcium current (ICa,L) in rat ventric-ular cardiomyocytes during hypoxia-reoxygenation to find out the mechanism of antiarrhythmic effect. Methods Whole-cell patch clamp was used to record ICa,L in the ventricular cardiomyocytes during hypoxia-reoxygenation in rat under amiodarone and different concentrations of TMCC. Results In hypoxia-reoxy-genation model, peak ICa,L increased from ( 3. 35 ± 0. 50 ) pA/pF to ( 5. 69 ± 0. 25 ) pA/pF ( n =6 , P 0. 05),(4. 41 ± 0. 22) pA/pF, (3. 82 ± 0. 21)pA/pF(n=6, P<0. 01) by TMCC(100, 200, 400 μmol·L-1 ) and amidodarone 24. 24 μmol·L-1 restored peak ICa,L to(3. 66 ± 0. 27)pA/pF (n=6,P<0. 01 ) . Compared to control group, hypoxia-reoxy-genation turned ICa,L steady-state activation curves to left and inactivation curves to right, which quickened activation and slowed inactivation, TMCC ( 200, 400μmol · L-1 ) and amiodarone could restore the left shift activation curves and right shift inactivation curves. Conclusion TMCC can concentration-de-pendently restore the increase of calcium current due to hypoxia-reoxygenation by promoting inactivation process and inhibiting activation process, and the effect is equal to that of amiodarone. TMCC blocks ICa,L of the ventricular cardiomyocytes, which may be one of its antiarrhythmic mechanisms.
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Aims To investigate the protective effects of noninvasive limb ischemic preconditioning (LIPC) on myocardial ischemia-reperfusion (I /R)injury,and to explore the mechanism.Methods Healthy male Wistar rats were divided randomly into I /R,I /R +LIPC,I /R +5-Hydroxydecanoate (5-HD)and I /R +LIPC +5-HD groups.The I /R +LIPC and I /R +LIPC-5-HD groups of rats were subjected to three cy-cles of LIPC induction per day with 5 min of reperfu-sion after occlusion for 5 min at the left hind limb for 3 days.All rats were subjected to myocardial I /R injury on the fourth day.The I /R +5-HD and I /R +LIPC-5-HD groups of rats were given the inhibitor of ATP-sen-sitive potassium channel 5-HD before and during myo-cardial I /R injury. Results Compared with I /R group,LIPC reduced myocardial infarct size (P <0.05),lowered cardiocyte apoptosis index and Fas, FasL positive cell number (P <0.01 ),increased the reduced nitric oxide (NO)/endothelin (ET)-1 ratio (P <0.05)in serum in I /R +LIPC group.5-HD a-bolished the protective effects induced by LIPC in I /R+LIPC-5-HD group.Compared with normal myocardi-al tissue,expression of mir-30a-3p was increased in I /R group (P <0.01 )and was decreased in LIPC group (P <0.01 ).Conclusion LIPC alleviates myocardial I /R injury and improves endothelial function. The mechanism may be related with the opening of ATP-sensitive potassium channel,regulating the balance be-tween NO and ET-1 and decreasing the expression of myocardial mir-30a-3p.
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Aim To investigate the protective effects of nicorandil, glutamine and metoprolol used in single and combination on the antiapoptosis ability of cardio-cytes and the expression of HSP70 after myocardial is-chemia/reperfusion injury in rats. Methods Male Wistar rats were divided randomly into seven groups:( 1 ) Sham group:in which the coronary artery was not roped;(2) I/R group:in which only 30 min ischemia and 120 min reperfusion of LAD was executed; ( 3 ) Nicorandil group; ( 4 ) Glutamine group; ( 5 ) Meto-prolol group; ( 6 ) Nic + Glu + Met ( NGM ) group;(7) low dose of Nic+Glu+Met ( NGML) group. In the pharmacological precondition groups, correspond-ing drugs were administered 30 min before I/R proto-col, and the initial drug dose in each group was 1 mg ·kg-1 . Myocardial apoptotic rates were measured with TUNEL ( terminal dexynucleotidyl transferase-mediated dUTP nick end labeling) , and the expression of apop-tosis related proteins-Bcl-2/Bax and protective pro-tein-HSP70 was detected by Western blot. ResultsIn I/R group, the apoptotic rate in ischemic region was very high ( 36.9% ± 10.3%) , and Bcl-2/Bax was very low ( 0.14 ±0.08 ) . Compared with I/R group, the apoptotic rate of pharmacological precondition groups was decreased significantly ( P <0.01 ) , and the ratio of Bcl-2 to Bax was raised ( P<0.01 ) . Com-pared with Sham group, the expression of HSP70 in-creased significantly ( P<0.01 ) in I/R group. Com-pared with IR group, the expression of HSP70 of phar-macological precondition groups was elevated ( P <0.01 ) , and the expression in NGM group was higher than in the single drug group ( P<0.01 ) . Conclusion Compared with single therapy after I/R in rat, the combination therapy of nicorandil, glutamine, meto-prolol can decrease the apoptotic rate, and the expres-sion of apoptosis related proteins is developed. In the mean time, the expression of protective protein HSP70 is elevated.
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Aim To investigate the antiarrhythmic mechanism of taurine-magnesium coordination com-pound on abnormal sodium current channel ( INa ) in-duced by hypoxia-reoxygenation in ventricular myocytes of rats. Methods Single ventricular myocytes were i-solated from each rat heart using enzymatic dissociation through Langendorff retrograde aortic perfusion. Whole-cell patch clamp was applied in voltage clamp mode to record INa both in normal ventricular myocytes and single ventricular myocytes of arrhythmia induced by hypoxia-reoxygenation. Results The peak density of INa was changed from ( 56. 89 ± 2. 07 ) pA/pF to (35. 05 ± 1. 52) pA/pF( n=6, P 0. 05), in a concentration-dependent manner, while amioda-rone restored it to (39. 44 ± 1. 24) pA/pF (n=6,P<0. 01 ) . Both high concentration of TMCC and amioda-rone could shift the I-V curve downward. In addition, TMCC and amiodarone could restore the INa inactivation curve and slow down its inactivation, whereas the acti-vation curves showed no significant differences among groups. Conclusion TMCC(200,400 μmol·L-1) could restore the H/R induced INa reduction and shift the I-V curve downward by inhibiting steady-state inac-tivation, which is suggested to be one of the mecha-nisms of the antiarrhythmic effects of TMCC in hypoxia-reoxygenation model.
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AIM: To study the effect of sphingosine 1-phosphate (S1P) on the increase in microvessel permeability induced by platelet activating factor (PAF). METHODS: The microvessel permeability was assessed by measuring hydraulic conductivity (Lp). To observe the effect of S1P and PAF on vascular endothelial-cadherin (VE-Cadherin), the microvessels were stained with immunofluorescence and examined by laser confocal microscopy. RESULTS: After giving PAF at concentration of 10 nmol/L, the Lp value of rat mesentery microvessel was significantly increased. However, after pretreatment with S1P, PAF did not give rise to a further significant change. The effect of PAF on microvascular endothelial cells could be seen: the formation of endothelial gap was induced, the microvascular fluorescence intensity significantly increased, a large number of fluorescent microspheres (FMs) distributed in the space among the endothelial cells. However, after pretreated with S1P, no obvious gap opening and the FMs accumulation were observed. Compared to normal control, no significant difference of the microvascular fluorescence intensity was found. CONCLUSION: PAF changes the structure of VE-Cadherin, leading to detachment of adherent junction, formation of intercellular gaps, which contributes to the increase in the permeability. S1P improves the increase in the microvessel permeability caused by PAF, which might be mediated by strengthening adherent junction and inhibiting the formation of endothelial gaps.
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The present study was to estimate pharmacokinetic parameters of metformin hydrochloride in 20 Chinese healthy volunteers with a limited sampling strategy (LSS), which will provide scientific data for bioequivalence and clinical application. A single dose of metformin was administrated to 20 healthy volunteers. The concentration of metformin in whole blood was determined by validated high performance liquid chromatography (HPLC) method. Multi-linear regression analysis was performed to establish a model to estimate AUC(0-24 h) and Cmax of metformin by LSS method. The LSS models were validated by the Jackknife method. The result indicated: the linearity relationship between AUC(0-24 h) or Cmax and single concentration point was poor. Several models for metformin AUC(0-24 h) or Cmax, estimation were better (r2 > 0.9, P < 0.05). Validation tests indicated that most informative sampling points (C2, C6 for AUC(0-24 h), C1.5, C2 for Cmax) provided accurate estimations of these parameters. So, a multi-linear regression model for estimation pharmacokinetic parameters of metformin by using LSS method is feasible.
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Cytochrome P450 is one of the important drug metabolization enzymes in humans. This paper reviews drug relevant CYP, the relationship of CYP and drug interaction, and effects of Chinese medicine on CYP. The aim is to answer and predict the clinical drug interaction and the adverse drug reactions. Moreover, suitable drug can be selected to evaluate the action of CYP, and it can offer the scientific assurance for clinical individual therapy.
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The method of simultaneous administration of several probe substrates is called “Cocktail" approaches. The objective of the article is to review the application of this technique in characterizing the activity of multiple drug-metabolizing enzymes and in clinical researches. This paper also shows Five-drug and Six-drug Cocktail set for evaluating in vivo activity of drug-metabolizing enzymes.
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Renin-angiotensin system (RAS) is correlative with many diseases. Angio tensin II (AngII) plays an important role as the final effective approach for RAS. This article reviews the main approach to the action and biosynthesis of AngII: including AngII receptor blocker (ARB), chymase inhibitor and ACE2 which were disscoverd recently.
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AIM To study the early cardioprotective effects of pharmacological preconditioning of nitroglycerin (NG) and buprenorphine (BU) used alone and in combination on myocardial ischemia in rats. METHODS Male Wistar rats were randomized to 5 groups. The ischemia and reperfusion injury was induced by ligation of the left arterior descending coronary arrery for 30 min and followed reperfusion for 2 h. The rats were subjected to different treatments before I/R. Normal saline (NS) was infused intravenously with the same volume of NG and BU in Sham group. Ischemia/preconditioning (IP) was performed by three cycles of 5 min I/R in EIP group. BU (1 0 mg?kg -1 ) and NG (0 3 mg?kg -1 ) was administered intravenously alone in BU and NG group or given together in B+N group to mimic the effects of IP, respectively. Heart rate, blood pressure, ST segment and arrhythmias were recorded continuously throughout the whole test. Plasma LDH and CK were measured on 30 min after ischemia and 2 h after reperfusion, HE and TTC staining were performed to determine myocardial necrosis at the end of test. RESULTS Compared with Sham group the onset of arrhythmias was delayed and the duration of ventricular premature contraction (VPC) was shortened remarkably ( P
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Endothelial glycocalyx is a hairy-like structure covered the endothelial cell surface,which consists of multiple functional elements.It has been proved that glycocalyx can regulate vascular permeability,mediate shear-induced release of NO by endothelial cells,and exert wide array of vasculoprotective effects via inhibition of coagulation and leucocyte adhesion.Degradation of glycocalyx may be associated with many cardiovascular diseases.In this review,the relationship between the endothelial glycocalyx and cardiovascular disease will be discussed.
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As a powerful endogenous protection,myocardial ischemic preconditioning and postconditioning have cardioprotection against ischemia reperfusion injury and cardiopretection against reperfusion injury respectively.They perhaps share some mechanisms during reperfusion,such as reduction of the production of oxygen free radical,activation of adenosine receptors,recruit of reperfusion injury salvage kinases,opening of the mitochondrial KATP channel,and inhibition of the mitochondrial permeability transition pore.These common targets may provide new strategy for development of drugs against reperfusion injury.
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Aim To study effects of different dosage regimens of gentamicin(GTM) on impairment of renal functions, plasma concentrations and pharmacokinetics in rats. Method 108 rats were divided into 6 groups: control group; chronological once-daily dose groups (N100 and D100 group, in which 100 mg?kg -1 GTM were intramuscularly administrated at 01 ∶00 or 13 ∶[KG-*3]00 respectively), and chronological twice-daily different dose groups (N90+D10, N70+D30, N50+D50 group, in which 90 mg?kg -1+10 mg?kg -1, 70 mg?kg -1+30 mg?kg -1 and 50 mg?kg -1+50 mg?kg -1 GTM were given at 1:00 and 13:00 respectively). The blood urea nitrogen (BUN) and creatinine (Cr) levels were observed, the plasma concentrations of GTM at 0.25,0.5,1, 2, 5 and 8h were determined, the C-T curves were profiled and the pharmacokinetic parameters were calculated at the 1st, the 10th, and the 20th day of administrations. Results ① Impairment of renal function. At the 10th day of administration, the Cr and BUN levels of N50+D50 group were the highest. There was a significant difference when compared those of the 10th day of administration with those of the 1st day of administration and of control group at same time respectively (P