OBJECTIVETo study the effect of gastrodin on isolated thoracic aorta rings of rats and to investigate the potential mechanism.

METHODSA perfusion model of isolated thoracic aorta rings of rats was applied. The effect of cumulative gastrodin (5, 50, 100,150, 200, and 250 μmol/L) on endothelium-intact aorta rings was investigated. The same procedure was applied to observe the effect of gastrodin on endothelium-intact/denuded aorta rings pre-contracted with 10(-6) mol/L phenylephrine hydrochloride (PE). The aorta rings incubated by 200 mmol/L gastrodin in the Ca(2+)-free (K-H) solution was contracted by using PE. The effect of 200 mmol/L gastrodin on endothelium-denuded aorta rings pre-contracted with 60 mmol/L KCl was also observed.

RESULTSCompared with the denuded gastrodin group, the intact gastrodin group could significantly relax the PE-contracted aorta rings (P<0.01). In Ca(2+)-free (K-H) solution KHS, the PE-induced contraction rate of aorta rings pre-incubated by gastrodin was 6.5%±0.7%, which was significantly less than the control group (11.8%±0.9%,P<0.01). However, after 3 mmol/L CaCl2 was added, the Ca(2+)-induced contraction in the gastrodin group (51.7%±2.4%) was similar to that in the control group (49.8%±2.8%). The contractile rate of rings in the KCl-contracted gastrodin group (96.3%±0.6%) was not significantly different from that in the control group (96.8%±1.2%).

CONCLUSIONSGastrodin has the effect of vasorelaxation on isolated thoracic aorta rings of rats. The mechanism of the vasorelaxation of gastrodin may mainly work through the inhibition of inositol 1, 4, 5-trisphosphosphate receptor on the sarcoplasmic reticulum of the arterial smooth muscle, which leads to the reduction of the Ca(2+) released from the sarcoplasmic reticulum.

Animals ; Aorta, Thoracic ; drug effects ; physiology ; Benzyl Alcohols ; pharmacology ; Calcium ; metabolism ; Endothelium, Vascular ; physiology ; Female ; Glucosides ; pharmacology ; In Vitro Techniques ; Male ; Phenylephrine ; pharmacology ; Rats ; Rats, Wistar ; Vasodilation ; drug effects

OBJECTIVECrassostrea gigas oyster extract has been reported to have antioxidant, antihypertensive and lipid-lowering properties that may be useful for treating cardiovascular diseases. This study aimed to evaluate the effect of C. gigas oyster extract on cardiovascular function in tissues from healthy rats.

METHODSSingle-cell microelectrode and isolated thoracic aortic organ bath studies were performed on tissues from 8-week-old healthy Wistar rats, using varying concentrations of C. gigas oyster extract. To elucidate a mechanism of action for the oyster's vasoactive properties, concentration response curves were carried out in the presence of a calcium channel inhibitior (verapamil), a nitric oxide synthase inhibitor (N(G)-nitro-L-arginine methyl ester), a potassium channel inhibitor (4-aminopyridine), in addition to the α-adrenoceptor inhibitor prazosin.

RESULTSOyster solution at 7 500 mg/mL inhibited noradrenaline-induced contraction in isolated aortic rings. Cardiac electrophysiology results showed that neither concentration of oyster solution was able to significantly reduce action potential duration at all phases of repolarisation in left ventricular papillary muscles from healthy animals.

CONCLUSIONWhen administered to healthy vascular tissue, C. gigas oyster extract inhibits contraction induced by noradrenaline. This effect is likely to be mediated through α-adrenoceptor inhibition, and to a lesser extent, calcium modulating activity.

Action Potentials ; drug effects ; Adrenergic alpha-Antagonists ; pharmacology ; Animals ; Aorta, Thoracic ; drug effects ; physiology ; Calcium ; metabolism ; Crassostrea ; Heart ; drug effects ; physiology ; Male ; Norepinephrine ; antagonists & inhibitors ; pharmacology ; Rats ; Rats, Wistar ; Vasoconstriction ; drug effects

OBJECTIVETo investigate the regulation on endothelial function of sapindus saponins in spontaneously hypertensive rats by studying the reactivity on different vasoconstrictor and dilator, and the content of the active substances.

METHODForty 16-week-old spontaneously hypertensive rats were randomly divided into five groups, one with placebo as model group, one with captopril tablets (27 mg x kg(-1)) as positive control, one with low-dose sapindus saponins (27 mg x kg(-1)), one with medium-dose (54 mg x kg(-1)), one with high-dose (108 mg x kg(-1)). And another eight healthy Wistar-Kyoto strain (WKY) rats were used as the normal group. The animals were treated for eight weeks, and the indicators to be detected were as follows: (1) the response of thoracic aorta on different vasoconstrictors Ang II (1 x 10(-9) -1 x 10(-5) mol x L(-1)), PE (1 x 10(-8) 1 x 10(-4) mol x L(-1)), KCl (20 -120 mmol x L(-1)); (2) the endothelium-dependent or non-endothelium-dependent vasodilation response of thoracic aorta on Ach (1 x 10-(10)-1 x 10(-5) mol x L(-1)) or SNP (1 x 10(-8)-1 x 10(-3) mol x (L(-1); (3) the content of NO, 6-KPG1alpha, ET-1 and TXB2 in serum was determined by Elisa.

RESULTIn SHR model group, the response of thoracic aorta on Ang II, PE and KCl was increased, the endothelium-dependent vasodilation on Ach was reduced, but the effects on SNP was not obvious, the content of ET-1 and TXB2 was increased, and the content of NO and 6-KPG1alpha was reduced, Vs the normal control group, there were significant differences (P < 0.05 or P < 0.01); in the treatment groups, the response of thoracic aorta on Ang II, PE and KCl was reduced, the endothelium-dependent vasodilation of thoracic aorta on Ach was improved, the content of ET-1 and TXB2 was reduced, and the content of NO and 6-KPG1alpha was increased, Vs the SHR model group, there were significant differences (P < 0.05 or P < 0.01).

CONCLUSIONOur findings suggested that sapindus saponins protected the endothelial function in SHR, the mechanisms were relevant to the protection of endothelial function.

Angiotensin II ; pharmacology ; Animals ; Aorta, Thoracic ; drug effects ; physiology ; Endothelin-1 ; analysis ; Endothelium, Vascular ; drug effects ; physiology ; Female ; Male ; Nitric Oxide ; analysis ; Rats ; Rats, Inbred SHR ; Rats, Inbred WKY ; Sapindus ; chemistry ; Saponins ; pharmacology

OBJECTIVETo investigate effects of dahuang zhechong pill ( DHZCP) on the cell cycle and the related signal pathways in vascular smooth muscle cells (VSMCs) stimulated by platelet-derived growth factor (PDGF) with the method of serum pharmacology.

METHODSDNA synthesis in VSMCs was examined by detecting 5'-bromo-2'-deoxyuridine incorporation with the immunocytochemical method. The cycle of VSMCs was evaluated with flow cytometry. Expressions of cyclin D1, p27, protein kinase Cα (PKCα), and phosphorylated extracellular signal regulated kinase 1/2 (ERK1/2) were quantified by Western blot method.

RESULTSDHZCP containing serum significantly inhibited DNA synthesis of PDGF-stimulated VSMCs, arrested the cells in G G(1) phase, modulated the protein expressions of cyclin D D(1) and p27, and suppressed the activation of PKCα and ERK1/2.

CONCLUSIONDHZCP containing serum inhibits VSMCs proliferation via modulating the expressions of cell cycle proteins to arrest the cell in G G(1) phase, which is attributed to, at least in part, suppressing PKCα-ERK1/2 signaling in VSMCs.

Animals ; Aorta, Thoracic ; cytology ; Blood Proteins ; pharmacology ; Cell Proliferation ; drug effects ; Cells, Cultured ; Cyclin D1 ; metabolism ; Cyclin-Dependent Kinase Inhibitor p27 ; metabolism ; DNA ; biosynthesis ; Drugs, Chinese Herbal ; pharmacology ; G1 Phase ; drug effects ; physiology ; MAP Kinase Signaling System ; physiology ; Male ; Muscle, Smooth, Vascular ; cytology ; drug effects ; enzymology ; Platelet-Derived Growth Factor ; pharmacology ; Protein Kinase C-alpha ; metabolism ; Rats ; Rats, Sprague-Dawley

OBJECTIVETo investigate the effect of gastrodin in relaxing isolated thoracic aorta rings in rats and discuss its possible mechanism.

METHODIsotonic tension of isolated thoracic aortic rings in rats with norepineprine (NE) and KCl was recorded to observe the vasodilatory effect of gastrodin and the influence of various drugs on it.

RESULTGastrodin had the effect in relaxing thoracic aortas with or without endothelium, and there was no significant difference. NG-nitro-L-argininemethylester (L-NAME, 1 x 10(-4) mol x L(-1)), methylene blue (MB, 1 x 10(-5) mol x L(-1)), indomethacin (INDO, 1 x 10(-5) mol x L(-1)) had no effect on the vasodilation action of gastrodin on thoracic aortas precontracted by NE. 4-aminopyrimide (4-AP, 1 x 10(-4) mol x L(-1)), tetrathylamonium (TEA, 1 x 10(-3) mol x L(-1)), BaCl2 (1 x 10(-4) mol x L(-1)) and glibenclamide (Gli, 1 x 10(-5) mol x L(-1)) could inhibit gastrodin's effect in relaxing thoracic aorta rings. In the absence of Ca2+, pre-incubated gastrodin showed a notable inhibitory effect in relaxing NE contraction.

CONCLUSIONGastrodin shows a dose-dependent and endothelium-independent effect in relaxing rat isolated thoracic aorta rings. The mechanism is related to K+ channel, inhibition of release of Ca+ stored in endoplasmic reticulum of vascular smooth muscle cells and inflow of external calcium Ca2+.

Animals ; Aorta, Thoracic ; drug effects ; physiology ; Benzyl Alcohols ; pharmacology ; Calcium ; metabolism ; Endothelium, Vascular ; physiology ; Glucosides ; pharmacology ; In Vitro Techniques ; Male ; Norepinephrine ; pharmacology ; Rats ; Rats, Sprague-Dawley ; Vasodilation ; drug effects

OBJECTIVETo investigate the effect of bicyclol on vascular oxidative stress injury induced by superoxide anion.

METHODSRat thoracic aortic rings were isolated for isometric tension recording using organ bath technique. Superoxide arterial injury was induced by pyrogallol exposure, and the effect of bicyclol on endothelium-dependent relaxation was evaluated.

RESULTSBicyclol (10(-8) - 10(-5) mol/L) relaxed endothelium-intact aortic rings precontracted by phenylephrine. This effect was abolished by L-NAME, an inhibitor of nitric oxide synthase and indomethacin, an inhibitor of cyclooxygenase. Exposure to pyrogallol (500 micromol/L) resulted in decrease of acetylcholine(ACh)-induced endothelium-dependent relaxation in aortic rings, and pre-incubation of bicyclol (10(-5) mol/L) for 45 min improved the relaxation attenuated by pyrogallol. In aortic rings pre-treated with indomethacin, bicyclol increased the ACh-induced relaxation that was inhibited by pyrogallol (500 micromol/L). This effect was not found in aortic rings pre-treated with L-NAME.

CONCLUSIONBicyclol has endothelium-dependent vasodilating effect on rat thoracic aorta and improves vascular function by attenuating oxidative stress. Nitric oxide from endothelium is involved in the anti-oxidative effect of bicyclol.

Animals ; Antioxidants ; pharmacology ; Aorta, Thoracic ; metabolism ; physiology ; Biphenyl Compounds ; pharmacology ; Endothelium, Vascular ; physiology ; In Vitro Techniques ; Male ; Oxidative Stress ; drug effects ; Pyrogallol ; pharmacology ; Rats ; Rats, Sprague-Dawley ; Superoxides ; pharmacology ; Vasodilation ; drug effects ; physiology

OBJECTIVETo examine the effect of puerarin on high glucose-induced decrease in contraction of isolated rat aortic rings, and to elucidate its underlying mechanism.

METHODSThe thoracic aortic rings with or without endothelium of male Sprague-Dawley rats were mounted on a bath system. Isometric contractions of aortic rings were measured. The activity of heme oxygenase-1 (HO-1) was also measured.

RESULTS(1) After incubation with 44 mmol/L of glucose (high glucose) for 4 h, the vascular contraction responses to phenylephrine (PE) decreased in an endothelium-dependent manner, when compared with the control group (containing 11 mmol/L of glucose). (2) After coincubation with puerarin ( 10(-10) - 10(-8) mol/L) and high glucose, the decrease in contraction responses to PE of arteries was partly inhibited in a dose-dependent manner. (3) After incubation with puerarin for 4 h, the HO-1 activity of thoracic aorta increased; ZnPP, an inhibitor of HO-1, abrogated the protection effect of puerarin.

CONCLUSIONPuerarin could prevent the high glucose-induced decrease in contraction responses to PE in intact aortic rings. The mechanism might be involved in the activation of HO-1.

Animals ; Aorta, Thoracic ; drug effects ; physiology ; Glucose ; pharmacology ; Heme Oxygenase (Decyclizing) ; metabolism ; In Vitro Techniques ; Isoflavones ; pharmacology ; Male ; Rats ; Rats, Sprague-Dawley ; Vasoconstriction ; drug effects ; Vasodilator Agents ; pharmacology

OBJECTIVETo investigate the vasodilative action and the possible mechanisms of Shenmai injection on porcine coronary artery.

METHODIsometric tensions of the porcine coronary artery ring precontracted with potassium chloride (KCl) were recorded in vitro when the doses of 0.1, 0.5, 1, 5, 10, 50 mL x L(-1) of Shenmai injective were cumulatively added into the organ bath of porcine coronary artery ring.

RESULTShenmai injection caused same vasorelaxation of porcine coronary artery rings with endothelium intact and denuded precontracted with KCl in a concentration-dependent manner. Pretreatment with TEA and 4-AP prohibited the vasorelaxation by Shenmai injection, but pretreatment with KB-R7943, BaCl2, Gli did not affect the vascular effect of Shenmai injection.

CONCLUSIONShenmai injection could produce vasodilatation on KCl pre-contracted porcine coronary artery rings. It seems that K(Ca) and K(V) channel play an important role in the relaxation of the porcine coronary artery rings pre-contracted with KCl.

Animals ; Aorta, Thoracic ; drug effects ; physiology ; Coronary Vessels ; drug effects ; physiology ; physiopathology ; Drugs, Chinese Herbal ; pharmacology ; Female ; In Vitro Techniques ; Male ; Nitric Oxide ; metabolism ; Swine ; Vasodilation ; drug effects ; Vasodilator Agents ; pharmacology

OBJECTIVETo investigate the vasorelaxation effect of crocetin (CCT) and its mechanism.

METHODSIsolated aortic rings from Sprague-Dawley rats were mounted in the organ bath system. The tension of the aorta was recorded.

RESULTCCT significantly provoked concentration-dependent relaxation in both endothelium-intact and-denuded aortic rings pre-constricted by phenylephrine (10⁻⁵ mol/L), and the vasorelaxation in endothelium-intact aortic rings was stronger than that in endothelium-denuded ones. CCT had no significant effects on aortic rings pre-constricted with KCl (6 × 10⁻² mol/L). Pretreatment with eith L-NAME (10⁻⁴ mol/L), an inhibitor of nitric oxide synthase (NOS), or indomethacin (10⁻⁵ mol/L), an inhibitor of cyclooxygenase, for 30 min significantly attenuated the relaxation of endothelium-intact aortic rings induced by CCT. Besides, both tetraethylammonium (a Ca²(+)-activated K(+) channel inhibitor, 5 × 10⁻³ mol/L) and 4-aminopyridine (a voltage-sensitive K(+) channel inhibitor, 10⁻³ mol/L), but not the ATP-sensitive K(+) channel inhibitor glibenclamide (3 × 10⁻⁶ mol/L), significantly attenuated CCT-induced relaxation in endothelium-denuded aortic rings.

CONCLUSIONCCT had partial endothelium-dependent relaxation in rat aortas, which may be mediated by activating the endothelial NOS-NO and cyclooxygenase-prostacyclin pathways. The endothelium-independent relaxation in rat aortas induced by CCT may be mediated by Ca²(+)-activated K(+) channels and voltage-sensitive K(+) channels.

Animals ; Aorta, Thoracic ; drug effects ; metabolism ; physiology ; Carotenoids ; pharmacology ; Endothelium, Vascular ; drug effects ; metabolism ; In Vitro Techniques ; Male ; Nitric Oxide ; metabolism ; Nitric Oxide Synthase ; metabolism ; Phenylephrine ; pharmacology ; Potassium Channel Blockers ; metabolism ; Rats ; Rats, Sprague-Dawley ; Vasodilation ; drug effects ; Vasodilator Agents ; pharmacology

Angiotensin II (AngII) is a crucial hormone that affects vasoconstriction and exerts hypertrophic effects on vascular smooth muscle cells. Here, we showed that phosphatidylinositol 3-kinase-dependent calcium mobilization plays pivotal roles in AngII-induced vascular constriction. Stimulation of rat aortic vascular smooth muscle cell (RASMC)-embedded collagen gel with AngII rapidly induced contraction. AngII-induced collagen gel contraction was blocked by pretreatment with a phosphatidylinositol 3-kinase (PI3K) inhibitor (LY294002) whereas ERK inhibitor (PD98059) was not effective. AngII-induced collagen gel contraction was significantly blocked by extracellular calcium depletion by EGTA or by nifedipine which is an L-type calcium channel blocker. In addition, AngII-induced calcium mobilization was also blocked by nifedipine and EGTA, whereas intracellular calcium store-depletion by thapsigargin was not effective. Finally, pretreatment of rat aortic ring with LY294002 and nifedipine significantly reduced AngII-induced constriction. Given these results, we suggest that PI3K-dependent activation of L-type calcium channels might be involved in AngII-induced vascular constriction.
1-Phosphatidylinositol 3-Kinase/*metabolism/pharmacology ; Angiotensin II/metabolism/*pharmacology ; Animals ; Aorta, Thoracic/*drug effects/physiology ; Calcium Channels, L-Type/drug effects/*metabolism ; Muscle Contraction/drug effects ; Muscle, Smooth, Vascular/drug effects/enzymology ; Rats ; Rats, Sprague-Dawley ; Signal Transduction/*drug effects ; Specific Pathogen-Free Organisms ; Vasoconstriction/*drug effects