OBJECTIVETo study the targeted point and mechanism of the function of the blood-activating and stasis-removing Chinese drugs, Paeoniae Radix 801(PR801) in its cardiovascular protective effects and its specific binding with endothelin 1 (ET-1) as well as the dynamics of the two's interactive function by means of using affinity biosensors: IAsys Plus and quartz crystal microbalance (IAQCM).

METHODSET-1 was immobilized on the surfaces of IAQCM by using the new surface modification methods. The PR801 in the solution was detected by modified substrates and the specific binding between PR801 and ET-1 was studied.

RESULTSThe curves went up or down after adding PR801. There is specific binding between PR801 and ET-1. The bound mass were 0.458 ng/mm(2) and 133.54 ng/cm(2), respectively. There exists relatively good stability with these two methods.

CONCLUSIONThe affinity biosensors: IAQCM can be used to study the interaction mechanism between PR801 and ET-1, providing a new way to study the interaction mechanism of TCM. PR801 can bind ET-1 specifically in the experiments. Therefore, ET-1 is another target that PR801 can bind specifically besides thromboxane A(2).

Biosensing Techniques ; standards ; Blood Circulation ; drug effects ; Drugs, Chinese Herbal ; metabolism ; therapeutic use ; Endothelin-1 ; metabolism ; Humans ; Quartz

No abstract available.
Blotting, Western ; Cells, Cultured ; Connective Tissue Cells/drug effects/metabolism ; Endothelin-1/*biosynthesis ; Fibroblasts/*drug effects/metabolism ; Humans ; Transforming Growth Factor beta1/*pharmacology

OBJECTIVETo study the effects of iptakalim (Ipt), an ATP-sensitive potassium channel opener, on cardiac remodeling induced by isoproterenol (ISO) in Wistar rats.

METHODSISO was given subcutaneously (85 mg/(kg x d), sc, 7 days) to induce cardiac remodeling in rats. The rats in Ipt treated group were administrated with Ipt 3 mg/kg (po) after ISO injection. After treated with Ipt for 6 weeks, the hemodynamic parameters were tested by an eight channel physiological recorder (RM-6000). Then the heart weight was weighed and the cardiac remodeling index was calculated. HE stain and Masson's stain were employed to perform histological analysis, the hydroxyproline(Hyp) content in cardiac tissue was detected by colorimetric method, radioimmunoassay was used to measure the plasma levels of endothelin-1 (ET-1) and prostacyclin (PGI2).

RESULTSSix weeks after ISO injection, the cardiac functions of model group were damaged markedly compared with those of normal group. The characteristics of ventricular remodeling in model group included that the heart weight index, myocyte cross-sectional area, myocardial fibrosis, and the hydroxyproline content in cardiac tissue were all increased significantly. The plasma level of ET-1 was increased, while the plasma level of PGI2 was decreased significantly. These changes could be reversed by Ipt treatment (3 mg/(kg x d) for 6 weeks).

CONCLUSIONIpt can reverse cardiac remodeling induced by isoproterenol in rats. The endothelial protective effect regulating effects of Ipt on the balance between the ET-1 and PGI2 system may be involved in its mechanisms.

Animals ; Endothelin-1 ; blood ; Hemodynamics ; Hydroxyproline ; metabolism ; Isoproterenol ; pharmacology ; KATP Channels ; drug effects ; Male ; Myocardium ; metabolism ; Propylamines ; pharmacology ; Prostaglandins I ; blood ; Rats ; Rats, Wistar ; Ventricular Remodeling ; drug effects

Endothelins (ETs), which were originally found to be potent vasoactive transmitters, were known to be implicated in nervous system, but the mode of mechanism remains unclear. ETs (ET-1, ET-2, and ET-3) were added to HN33 (mouse hippocampal neuron chi neuroblastoma) cells. Among the three types of ET, only ET-1 increased the intracellular calcium levels in a PLC dependent manner with the induction of ERK 1/2 activation. As the result of ET-1 exposure, the survival rate of HN33 cells and the PKCalpha translocation into the plasma membrane were increased. We suggest that ET-1 participated in the neuroprotective effect involving the calcium-PKCalpha-ERK1/2 pathway.
Animals ; Apoptosis/*drug effects ; Calcium/*metabolism ; Cell Line ; Cell Survival/drug effects ; Cytosol/drug effects/metabolism ; Endothelin-1/*pharmacology ; Endothelin-2/pharmacology ; Endothelin-3/pharmacology ; Estrenes/pharmacology ; Extracellular Signal-Regulated MAP Kinases/*metabolism ; Immunoblotting ; Mice ; Mitogen-Activated Protein Kinase 1/metabolism ; Mitogen-Activated Protein Kinase 3/metabolism ; Neurons/*cytology/drug effects/*enzymology ; Neuroprotective Agents/pharmacology ; Phosphoproteins/metabolism ; Protein Kinase C-alpha/*metabolism ; Protein Transport/drug effects ; Pyrrolidinones/pharmacology ; Serum

OBJECTIVETo study the expression of ET receptor and the apoptosis after intervened with ET receptor antagonist in androgen-independent prostate cancer.

METHODSPC3, an androgen-independent prostate cancer cell line, was used. The expression of ETA and ETB receptor in PC3 was measured through RT-PCR. After intervened with selective ETA and ETB receptor antagonist, the apoptosis in PC3 was studied through flow cytometry and electron microscope.

RESULTSClear signal was obtained in PC3 for ETA receptor mRNA transcript, while the signal for ETB receptor mRNA transcript was very weak. The expression of ETA receptor mRNA was obviously reduced and the apoptosis of PC3 cell was observed after intervened with selective ETA receptor antagonist. There was no change after intervened with selective ETB receptor antagonist.

CONCLUSIONET-1 exerts its effects through the ETA receptor subtype and ETB receptor is silenced in PC3. The expression of ETA was reduced and the apoptosis was observed in PC3 when ETA receptor was blocked. It was dose-dependent.

Androgens ; physiology ; Apoptosis ; drug effects ; physiology ; Endothelin A Receptor Antagonists ; Endothelin B Receptor Antagonists ; Endothelin-1 ; physiology ; Humans ; In Vitro Techniques ; Male ; Neoplasms, Hormone-Dependent ; pathology ; Oligopeptides ; administration & dosage ; Peptides, Cyclic ; administration & dosage ; Piperidines ; administration & dosage ; Prostatic Neoplasms ; pathology ; physiopathology ; Receptor, Endothelin A ; metabolism ; physiology ; Receptor, Endothelin B ; metabolism ; physiology

Hypoxic pulmonary hypertension (HPH) is a syndrome characterized by the increase of pulmonary vascular tone and the structural remodeling of peripheral pulmonary arteries. The aim of specific therapies for hypoxic pulmonary hypertension is to reduce pulmonary vascular resistance, reverse pulmonary vascular remodeling, and thereby improving right ventricular function. Iptakalim, a lipophilic para-amino compound with a low molecular weight, has been demonstrated to be a new selective ATP-sensitive potassium (K(ATP)) channel opener via pharmacological, electrophysiological, biochemical studies, and receptor binding tests. In hypoxia-induced animal models, iptakalim decreases the elevated mean pressure in pulmonary arteries, and attenuates remodeling in the right ventricle, pulmonary arteries and airways. Furthermore, iptakalim has selective antihypertensive effects, selective vasorelaxation effects on smaller arteries, and protective effects on endothelial cells, but no effects on the central nervous, respiratory, digestive or endocrine systems at therapeutic dose. Our previous studies demonstrated that iptakalim inhibited the effects of endothelin-1, reduced the intracellular calcium concentration and inhibited the proliferation of pulmonary artery smooth muscle cells. Since iptakalim has been shown safe and effective in both experimental animal models and phase I clinical trials, it can be a potential candidate of HPH in the future.
Animals ; Antihypertensive Agents ; therapeutic use ; Calcium ; metabolism ; Disease Models, Animal ; Endothelin-1 ; metabolism ; Hypertension, Pulmonary ; drug therapy ; Hypoxia ; drug therapy ; KATP Channels ; drug effects ; Myocytes, Smooth Muscle ; cytology ; drug effects ; Propylamines ; therapeutic use ; Pulmonary Artery ; drug effects

OBJECTIVETo study the effect of endothelin-1 (ET-1) and its antagonists on the expression of endothelin and its receptors mRNA in HSC-T6 cells.

METHODSCultured HSC-T6 cells were randomly divided into 7 groups: Sham control group, ET-1 group (10 nmol/L ET-1), BQ-123 group [1 micromol/L BQ-123, a selective endothelin receptor A (ETRA) antagonist], BQ-788 group [1 micromol/L BQ-788, a selective endothelin receptor B (ETRB) antagonist], ET-1 + BQ123 group (10 nmol/L ET-1 + 1 micromol/L BQ-123), ET-1 + BQ-788 group (10 nmol/L ET-1 + 1 micromol/L BQ-788) and ET-1 + BQ-788 group (10 nmol/L ET-1 + 1 micromol/L BQ-123 + 1 micromol/L BQ-788). The expression of endothelin receptor mRNA of HSC-T6 cells was determined by reverse-transcription polymerase chain reaction (RT-PCR).

RESULTSThe expression of ETRA mRNA in ET-1 + BQ123 + BQ788 and ET-1 + BQ788 group was significantly lower than ET-1 group (0.329 +/- 0.044 and 0.292 +/- 0.023 vs. 0.440 +/- 0.030 P < 0.05). Compared with ET-1 group, the expression of ETRB mRNA in ET-1 + BQ788 group was down regulated obviously (0.499 +/- 0.136 vs. 0.153 +/- 0.071, P < 0.05). There was no significant difference in ET-1 + BQ123 group and ET-1 + BQ123 + BQ788 group when compared with ET-1 group (0.499 +/- 0.136 vs. 0.496 +/- 0.103 and 0.299 +/- 0.129, P > 0.05).

CONCLUSIONSET-1 has no obvious effect on the expression of ETRA mRNA in HSC-T6. ET-1 may up-regulate the expression of ETRB mRNA. Act on ETRA receptor, ET-1 can inhibit the expression of ETRB mRNA.

Animals ; Cells, Cultured ; Endothelin-1 ; pharmacology ; Gene Expression Regulation ; drug effects ; Hepatocytes ; drug effects ; metabolism ; Oligopeptides ; pharmacology ; Peptides, Cyclic ; pharmacology ; Piperidines ; pharmacology ; RNA, Messenger ; genetics ; Rats ; Rats, Sprague-Dawley ; Receptor, Endothelin A ; biosynthesis ; drug effects ; genetics ; Receptor, Endothelin B ; biosynthesis ; drug effects ; genetics

The effects of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase inhibitor apocynin on the enhanced hypoxia induced factor-1α (HIF-1α) and endothelin-1 (ET-1) expression, elevated systolic blood pressure under chronic intermittent hypoxia (CIH) condition and its action mechanism were investigated. Thirty healthy 8-week old Sprague-Dawley (SD) male rats were randomly divided into three groups (n=10 each): sham group, CIH group, and apocynin-treated CIH group. Tail artery systolic blood pressure was measured by tail-cuff method. Real-time fluorescence quantitative polymerase chain reaction (PCR) was used to detect the mRNA expression of HIF-1α and ET-1 in the carotid body, and the HIF-1α protein expression was examined by using Western blotting. The levels of malondialdehyde (MDA) and superoxide dismutase (SOD) were determined by using colorimetric method. In addition, the plasma ET-1 and HIF-1α levels were measured by using enzyme-linked immunosorbent assay. It was found that CIH exposure was associated with increased MDA levels, and apocynin-treated CIH animals showed reduction in MDA levels. Apocynin treatment prevented CIH-induced hypertension as well as CIH-induced decrease in SOD. The increases of HIF-1α and ET-1 mRNA along with HIF-1α protein expression in the carotid body, and elevated circulating HIF-1α and ET-1 levels were observed in CIH-exposed animals. Treatment with apocynin significantly decreased the ET-1 mRNA, HIF-1α protein expression and circulating HIF-1α level in CIH-exposed animals, and there was no statistically significant difference in the HIF-1α mRNA expression between CIH group and apocynin-treated group. These results indicated that apocynin alleviated CIH-induced hypertension by inhibiting NADPH oxidase, further leading to the reduced vasoconstrictor ET-1 level and oxidative stress. HIF-1α/ET-1 system signal pathway may interact with CIH-induced NADPH oxidase-dependent oxidative stress. Inhibition of NADPH oxidase activity may hopefully serve as a useful strategy for prevention and treatment of obstructive sleep apnea hypopnea syndrome-induced hypertension.
Acetophenones ; administration & dosage ; Animals ; Antioxidants ; administration & dosage ; Carotid Body ; drug effects ; metabolism ; Endothelin-1 ; metabolism ; Hypoxia ; drug therapy ; metabolism ; Hypoxia-Inducible Factor 1, alpha Subunit ; metabolism ; Male ; NADP ; antagonists & inhibitors ; Rats ; Rats, Sprague-Dawley ; Reactive Oxygen Species ; metabolism ; Treatment Outcome

OBJECTIVETo investigate the effect of Shenmai injection on vascular endothelial active facters nitric oxide (NO) and endothelin-1 (ET-1), and pulmonary gas exchange induced by tourniquet deflation in patients undergoing lower extremity surgery.

METHODTwenty-six patients scheduled for unilateral lower extremity surgery were randomly divided into 2 groups: control group (group C, n = 14) and Shenmai injection group (group SM, n = 12). All the patients agreed to a combined spinal-epidural anesthesia at the L2-L3 interspace and a radial artery catheter was placed for sampling. Patients in group SM were injected Shenmai injection 0.6 mL x kg(-1) and physiological saline 100 mL, while patients in group C were injected equal volume of normal saline instead 15 min before tourniquet inflation. Blood samples which were used for blood gas analysis and measurement of nitric oxide (NO) and endothelin-1 (ET-1) were taken before tourniquet inflation (T0, baseline) and 30 min (T1), 2 h (T2), 6 h (T3), 24 h (T4) after tourniquet deflation.

RESULTCompared with the baseline values at T0, in group C at T3 P(a) O2 and the levels of NO were significantly decreased, while P(A-a) DO2 and the levels of ET-1 at T3 were significantly increased (P < 0.05 or P < 0.01), in group SM, the levels of NO at T3 were significantly decreased (P < 0.05). Compared with group C, the changes of P(a)O2, P(A-a) DO2, NO and ET-1 were significantly mitigated in group SM.

CONCLUSIONThe concentrations of NO and ET-1 is connected with the pulmonary gas exchange impairment induced by tourniquet application. Shenmai injection can improve the pulmonary gas exchange based on rising the level of NO, reducing the level of ET-1.

Adult ; Drug Combinations ; Drugs, Chinese Herbal ; administration & dosage ; pharmacology ; Endothelin-1 ; blood ; metabolism ; Endothelium, Vascular ; drug effects ; metabolism ; physiopathology ; Female ; Humans ; Injections, Intravenous ; Male ; Middle Aged ; Nitric Oxide ; blood ; metabolism ; Pulmonary Gas Exchange ; drug effects ; Tourniquets ; adverse effects

OBJECTIVETo explore the relationship of gentamicin-induced cochlear damage with autophagy-related protein LC3, beclin1, Na(+-)K(+-)2Cl(-) cotransporter (NKCC1) mRNA and endothelin-1 (ET-1), and investigate the protective mechanism of PPTA against gentamicin-induced cochlear damage.

METHODSSixty guinea pigs were randomly divided into control group (with saline and artificial perilymph injections), model group (with gentamicin and artificial perilymph injections), concurrent treatment group (with gentamicin and PPTA injections), model control group (with artificial perilymph injection 7 days after gentamicin injection) and delayed treatment group (with PPTA injection 7 days after gentamicin injection). Saline and gentamicin (160 mg/kg) were injected intraperitoneally, and artificial perilymph and PPTA were injected into the otocysts on a daily basis for 7 consecutive days. Hearing impairment of the guinea pigs was analyzed with ABR, and the protein expressions of beclin1 and LC3 in cochlear tissue were tested. The expression of NKCC1 mRNA was detected with RT-PCR, and the expression of ET-1 was detected immunohistochemically.

RESULTSThe ABR thresholds in the model group and model control group were similar (P>0.05) , but significantly higher than those in the other 3 groups (P<0.05); the threshold was significantly lower in concurrent treatment group than in delayed treatment group (P<0.05). Compared with those in the other 4 groups, the expressions of LC3 II, beclin1, and NKCC1 mRNA were significantly increased in the model group (P<0.05); and those in delayed treatment group were significantly lower than those in the model control group (P<0.05). The expressions of ET-1 in the Corti organ, striavascularis and spiral ganglion were significantly higher in the model group but significantly lower in the control group than those in the other 4 groups; ET-1 expression was significantly lower in delayed treatment group than in the model control group.

CONCLUSIONPPTA offers protection against gantamicin-induced cochlear damage in guinea pigs by inhibiting cell autophagy and suppressing of NKCC1 and ET-1 expressions. Early intervention with PPTA produces better therapeutic effect, suggesting that gantamicin causes irreversible injury of the auditory cells.

3,4-Methylenedioxyamphetamine ; analogs & derivatives ; pharmacology ; Animals ; Apoptosis Regulatory Proteins ; metabolism ; Beclin-1 ; Cochlea ; drug effects ; Endothelin-1 ; metabolism ; Gentamicins ; adverse effects ; Guinea Pigs ; Hearing Loss ; chemically induced ; prevention & control ; Microtubule-Associated Proteins ; metabolism ; Solute Carrier Family 12, Member 2 ; metabolism