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1.
Kaohsiung J Med Sci ; 22(4): 184-8, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16679300

RESUMO

During percutaneous coronary intervention, entrapment of catheter materials is a rare but life-threatening complication that sometimes requires emergency surgical treatment. Coronary artery stents have been developed to prevent acute coronary closure and reduce restenosis after coronary angioplasty. The most frequently reported complications of coronary stents are related to stent thrombosis and anticoagulation problems. This case study describes a 60-year-old female who had stable angina pectoris and underwent stent insertion into the left circumflex artery. Unfortunately, the coronary stent with balloon catheter was entrapped while crossing the angulated segment between the left circumflex and left main coronary artery. The stent catheter was surgically removed, and the patient underwent coronary artery bypass grafting successfully. Physicians should keep in mind that extremely angulated segments may reduce the successful rate of coronary stenting and contribute to the stent entrapment complication.


Assuntos
Angioplastia Coronária com Balão/efeitos adversos , Doença das Coronárias/terapia , Stents/efeitos adversos , Angioplastia Coronária com Balão/instrumentação , Cateterismo , Feminino , Humanos , Pessoa de Meia-Idade
2.
J Pharmacol Exp Ther ; 316(2): 709-17, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16234412

RESUMO

KMUP-3 (7-[2-[4-(4-nitrobenzene)piperazinyl]ethyl]-1,3-dimethylxanthine) was investigated in guinea pig tracheal smooth muscle. Intratracheal instillation of tumor necrosis factor (TNF)-alpha (0.01 mg/kg/300 microl) induced bronchoconstriction, increases of lung resistance, and decreases of dynamic lung compliance. Instillation of KMUP-3 (0.5-2.0 mg/kg) reversed this situation. In isolated trachea precontracted with carbachol, KMUP-3 (10-100 microM)-caused relaxations were attenuated by epithelium removal and by pretreatments with an inhibitor of K(+) channel, tetraethylammonium (10 mm); K(ATP) channel, glibenclamide (1 microM); voltage-dependent K(+) channel, 4-aminopyridine (100 microM); Ca(2+)-dependent K(+) channel, charybdotoxin (0.1 microM) or apamin (1 microM); soluble guanylate cyclase (sGC), 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1one (ODQ, 1 microM); nitric-oxide (NO) synthase, N(omega)-nitro-L-arginine methyl ester (L-NAME, 100 microM); and adenylate cyclase, SQ 22536 [9-(terahydro-2-furanyl)-9H-purin-6-amine] (100 microM). KMUP-3 (0.01-100 microM) induced increases of cGMP and cAMP in primary culture of tracheal smooth muscle cells (TSMCs). The increase in cGMP by KMUP-3 was reduced by ODQ and L-NAME; the increase in cAMP was reduced by SQ 22536. Western blot analysis indicated that KMUP-3 (1 microM) induced expression of protein kinase A (PKA)(ri) and protein kinase G (PKG)(1alpha 1beta) in TSMCs.SQ 22536 inhibited KMUP-3-induced expression of (PKA)(ri). On the contrary, ODQ inhibited KMUP-3-induced expression of PKG(1alpha 1beta) In epithelium-intact trachea, KMUP-3 increased the NO release. Activation of sGC, NO release, and inhibition of phosphodiesterases in TSMCs by KMUP-3 may result in increases of intracellular cGMP and cAMP, which subsequently activate PKG and PKA, efflux of K(+) ion, and associated reduction in Ca(2+) influx in vitro, indicating the action mechanism to protect against TNF-alpha-induced airway dysfunction in vivo.


Assuntos
Proteínas Quinases Dependentes de GMP Cíclico/biossíntese , GMP Cíclico/biossíntese , Contração Muscular/efeitos dos fármacos , Óxido Nítrico/metabolismo , Piperidinas/farmacologia , Respiração/efeitos dos fármacos , Traqueia , Xantinas/farmacologia , Adenilil Ciclases/metabolismo , Animais , Cobaias , Técnicas In Vitro , Masculino , Músculo Liso/efeitos dos fármacos , Músculo Liso/enzimologia , Músculo Liso/metabolismo , Diester Fosfórico Hidrolases/metabolismo , Canais de Potássio/metabolismo , Traqueia/efeitos dos fármacos , Traqueia/enzimologia , Traqueia/metabolismo , Fator de Necrose Tumoral alfa/farmacologia
3.
Kaohsiung J Med Sci ; 21(11): 517-21, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16358554

RESUMO

Aneurysm of the sinus of Valsalva (ASV), frequently associated with ventricular septal defect (VSD), is a rare cardiac disease that may be acquired or congenital. Rupture of an ASV, rare in the noncoronary cusp, usually produces serious hemodynamic change and carries poor prognosis if not treated surgically. We present the case of a 55-year-old female who came to us complaining of exertional dyspnea. Transthoracic echocardiography and aortography showed a noncoronary cusp ASV with rupture into the right atrium but without VSD. Because of high left to right shunt flow, she underwent successful surgical intervention with aneurysm repair approached from both the aorta and right atrium with a knitted Dacron patch. This was a rare case of noncoronary cusp involvement in ASV that ruptured into the right atrium without VSD.


Assuntos
Aneurisma Roto/diagnóstico , Aneurisma Aórtico/diagnóstico , Ruptura Aórtica/diagnóstico , Seio Aórtico , Aneurisma Roto/cirurgia , Aneurisma Aórtico/cirurgia , Ruptura Aórtica/cirurgia , Aortografia , Ecocardiografia , Feminino , Átrios do Coração , Humanos , Pessoa de Meia-Idade
4.
J Cardiovasc Pharmacol ; 46(2): 130-40, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16044023

RESUMO

Intravenous and oral labedipinedilol-C showed a dose-dependent long-lasting hypotension and a decrease of heart rate in normotensive and conscious spontaneously hypertensive rats (SHR). In isolated Wistar rat and guinea pig tissues, labedipinedilol-C competitively antagonized (-)isoproterenol-induced cardiac stimulation, tracheal relaxation, and phenylephrine-, CaCl2-, and high-K-induced aorta contractions in a concentration-dependent manner. The estimated pA2 and pKCa values were 8.22+/-0.04 and 7.11+/-0.52, respectively. [H]CGP-12177 binding to ventricle and lung tissues as well as [H]prazosin and [H]nitrendipine binding to brain membranes were inhibited by labedipinedilol-C with Ki values of 2.86, 9.03, 0.39, and 0.05 muM, respectively. The vasorelaxant effects of labedipinedilol-C on phenylephrine (10 microM)-induced contractions were attenuated by removing endothelium, by pretreatment with soluble guanylyl cyclase (sGC) inhibitors ODQ (10 microM) and methylene blue (10 microM), a NOS inhibitor L-NAME (100 microM), a K channel blocker TEA (10 mM), a KATP channel blocker glibenclamide (1 microM), and Ca-dependent K channel blockers apamin (1 microM) and charybdotoxin (0.1 microM). In human umbilical vein endothelial cells (HUVECs), labedipinedilol-C increased NO release, which was significantly inhibited by L-NAME. The Western blot analysis on HUVECs indicated that labedipinedilol-C increased the expression of eNOS. These results indicate that hypotension effects of labedipinedilol-C result from alpha-adrenoceptor and Ca entry-blocking activities and release of NO or NO-related substance from vascular endothelium. The endothelium-independent relaxation of vascular smooth muscle is probably linked to K channel opening and alpha-adrenoceptor-blocking activities.


Assuntos
Antagonistas Adrenérgicos/farmacologia , Bloqueadores dos Canais de Cálcio/farmacologia , Di-Hidropiridinas/farmacologia , Hipertensão , Óxido Nítrico/metabolismo , Piperazinas/farmacologia , Canais de Potássio/metabolismo , Antagonistas Adrenérgicos/administração & dosagem , Antagonistas Adrenérgicos/uso terapêutico , Animais , Aorta/efeitos dos fármacos , Ligação Competitiva , Pressão Sanguínea/efeitos dos fármacos , Bloqueadores dos Canais de Cálcio/administração & dosagem , Bloqueadores dos Canais de Cálcio/uso terapêutico , Linhagem Celular , Di-Hidropiridinas/administração & dosagem , Di-Hidropiridinas/uso terapêutico , Cobaias , Frequência Cardíaca/efeitos dos fármacos , Humanos , Hipertensão/tratamento farmacológico , Hipertensão/metabolismo , Hipertensão/fisiopatologia , Técnicas In Vitro , Ativação do Canal Iônico/efeitos dos fármacos , Piperazinas/administração & dosagem , Piperazinas/uso terapêutico , Ensaio Radioligante , Ratos , Ratos Endogâmicos SHR , Ratos Wistar , Receptores Adrenérgicos alfa/metabolismo , Receptores Adrenérgicos beta/metabolismo , Traqueia/efeitos dos fármacos , Vasoconstritores/farmacologia , Vasodilatação/efeitos dos fármacos
5.
Life Sci ; 76(8): 931-44, 2005 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-15589969

RESUMO

The vasorelaxation activities of MCPT, a newly synthesized xanthine derivative, were investigated in this study. In phenylephrine (PE)-precontracted rat aortic rings with intact endothelium, MCPT caused a concentration-dependent relaxation, which was inhibited by endothelium removed. This relaxation was also reduced by the presence of nitric oxide synthase inhibitor Nomega-nitro-L-arginine methylester (L-NAME, 100 microM), soluble guanylyl cyclase (sGC) inhibitors methylene blue (10 microM), 1 H-[1,2,4] oxidazolol [4,3-a] quinoxalin-1-one (ODQ, 1 microM), adenylyl cyclase (AC) blocker SQ 22536 (100 microM), ATP-sensitive K+ channel blocker (KATP) glibenclamide (1 microM), a Ca2+ activated K+ channels blocker tetraethylammonium (TEA, 10 mM) and a voltage-dependent potassium channels blocker 4-aminopyridine (4-AP, 100 microM). The vasorelaxant effects of MCPT together with IBMX (0.5 microM) had an additive action. In PE-preconstricted endothelium-denuded aortic rings, the vasorelaxant effects of MCPT were attenuated by pretreatments with glibenclamide (1 microM), SQ 22536 (100 microM) or ODQ (1 microM), respectively. MCPT enhanced cAMP-dependent vasodilator isoprenaline- and NO donor/cGMP-dependent vasodilator sodium nitroprusside-induced relaxation activities in endothelium-denuded aortic rings. In A-10 cell and washed human platelets, MCPT induced a concentration-dependent increase in intracellular cyclic GMP and cyclic AMP levels. In phosphodiesterase assay, MCPT displayed inhibition effects on PDE 3, PDE 4 and PDE 5. The inhibition % were 52 +/- 3.9, 32 +/- 2.6 and 8 +/- 1.1 respectively. The Western blot analysis on HUVEC indicated that MCPT increased the expression of eNOS. It is concluded that the vasorelaxation by MCPT may be mediated by the inhibition of phosphodiesterase, stimulation of NO/sGC/ cGMP and AC/cAMP pathways, and the opening of K+ channels.


Assuntos
Músculo Liso Vascular/efeitos dos fármacos , Nucleotídeos Cíclicos/metabolismo , Compostos Organotiofosforados/farmacologia , Inibidores de Fosfodiesterase/metabolismo , Canais de Potássio/metabolismo , Vasodilatação/efeitos dos fármacos , Animais , Aorta Torácica/efeitos dos fármacos , Aorta Torácica/metabolismo , AMP Cíclico/metabolismo , GMP Cíclico/metabolismo , Relação Dose-Resposta a Droga , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Técnicas In Vitro , Músculo Liso Vascular/metabolismo , Ratos
6.
J Cardiovasc Pharmacol ; 44(5): 539-51, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15505490

RESUMO

Labedipinedilol-A is a novel 1, 4-dihydropyridine type calcium antagonist with alpha-receptor blocking activity. This study investigates the effects of labedipinedilol-A on mitogen-induced proliferation of rat vascular smooth muscle cells (VSMCs). Labedipinedilol-A's inhibition on cell proliferation was measured by the tetrazolium salt (XTT) test. Labedipinedilol-A dose-dependently inhibited mitogen-induced DNA synthesis, determined by the incorporation of 5-bromo-2'-deoxyuridine (BrdU). Labedipinedilol-A was also found capable of inhibiting the migration of VSMCs induced by PDGF-BB with an IC50 value of 5.6 microM. In accordance with these findings, labedipinedilol-A revealed blocking of the FBS-inducible progression through G0/G1 to S phase of the cell cycle in synchronized cells. Labedipinedilol-A appeared to cause inhibition of mitogens-induced PKC translocation, suggesting the probable involvement of protein kinase C (PKC) in this cellular response. Labedipinedilol-A reduced both intracellular Ca and the phosphorylation of extracellular signal-regulated protein kinase 1/2 in PDGF-BB-stimulated VSMCs. It also suppressed the levels of proliferative cell nuclear antigen (PCNA) in VSMCs both time- and dose-dependently. These results indicate that labedipinedilol-A may inhibit cell proliferation by attenuating activation of the ERK 1/2 pathway, which is regulated by PKC and Ca, suggesting that it may have great potential in the prevention of progressive atherosclerosis.


Assuntos
Anisóis/farmacologia , Di-Hidropiridinas/farmacologia , Proteína Quinase 1 Ativada por Mitógeno/antagonistas & inibidores , Músculo Liso Vascular/patologia , Proteína Quinase C/metabolismo , Animais , Anisóis/metabolismo , Aorta Torácica/patologia , Bromodesoxiuridina/farmacologia , Cálcio/metabolismo , Técnicas de Cultura de Células , Movimento Celular/efeitos dos fármacos , Movimento Celular/genética , Proliferação de Células/efeitos dos fármacos , China , DNA/antagonistas & inibidores , DNA/metabolismo , Di-Hidropiridinas/química , Di-Hidropiridinas/metabolismo , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos/métodos , Quinase 2 de Adesão Focal , Humanos , Interfase/efeitos dos fármacos , Isoenzimas/química , Isoenzimas/metabolismo , MAP Quinase Quinase 2 , Masculino , Proteína Quinase 1 Ativada por Mitógeno/efeitos dos fármacos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Fosforilação/efeitos dos fármacos , Fator de Crescimento Derivado de Plaquetas/metabolismo , Fator de Crescimento Derivado de Plaquetas/farmacologia , Antígeno Nuclear de Célula em Proliferação/efeitos dos fármacos , Antígeno Nuclear de Célula em Proliferação/genética , Antígeno Nuclear de Célula em Proliferação/metabolismo , Prolina/química , Proteína Quinase C/química , Proteínas Tirosina Quinases/química , Proteínas Tirosina Quinases/metabolismo , Ratos , Ratos Wistar , Veias Umbilicais/efeitos dos fármacos , Veias Umbilicais/metabolismo , Veias Umbilicais/patologia
7.
Ultrasound Med Biol ; 30(8): 1063-6, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15474750

RESUMO

To evaluate if pericardium is a suitable calibration reference in the integrated backscatter (IBS) analysis, the grossly normal pericardial specimens from 23 patients without a history of pericarditis were mounted on a steel platform and immersed in a 0.9% saline bath. The 2-D IBS images acquired at the uniform time gain compensation settings of 50 and 70 dB were analyzed. For the pericardial IBS, the limits of agreement for intraobserver and interobserver measurements were -1.2 to 1.4 dB and -1.6 to 2.2 dB, respectively. However, the calibrated IBS intensity of the pericardium presented a rather wide range of variation and was -13 +/- 5 (-5 to -29) and -10 +/- 4 (-4 to -22) dB at the overall gain settings of 50 and 70 dB, respectively. Conclusively, pericardium may not be an ideal IBS calibration reference in a population study of cardiac tissue characterization.


Assuntos
Ecocardiografia/normas , Pericárdio/diagnóstico por imagem , Idoso , Envelhecimento/fisiologia , Calibragem , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade
8.
Br J Pharmacol ; 142(7): 1105-14, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15237094

RESUMO

7-[2-[4-(2-chlorophenyl)piperazinyl]ethyl]-1,3-dimethylxanthine (KMUP-1) produces tracheal relaxation, intracellular accumulation of cyclic nucleotides, inhibition of phosphodiesterases (PDEs) and activation of K+ channels. KMUP-1 (0.01-100 microm) induced concentration-dependent relaxation responses in guinea-pig epithelium-intact trachea precontracted with carbachol. Relaxation responses were also elicited by the PDE inhibitors theophylline, 3-isobutyl-1-methylxanthine (IBMX), milrinone, rolipram and zaprinast (100 microm), and a KATP channel opener, levcromakalim. Tracheal relaxation induced by KMUP-1 was attenuated by epithelium removal and by pretreatment with inhibitors of soluble guanylate cyclase (sGC) (1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ), 1 microm), nitric oxide synthase (Nomega-nitro-L-arginine methyl ester, 100 microm), K+ channels (tetraethylammonium, 10 mm), KATP channels (glibenclamide, 1 microm), voltage-dependent K+ channels (4-aminopyridine, 100 microm) and Ca2+-dependent K+ channels (charybdotoxin, 0.1 microm or apamin, 1 microm). Both KMUP-1 (10 microm) and theophylline nonselectively and slightly inhibited the enzyme activity of PDE3, 4 and 5, suggesting that they are able to inhibit the metabolism of adenosine 3',5'-cyclic monophosphate (cyclic AMP) and guanosine 3',5'-cyclic monophosphate (cyclic GMP). Likewise, the effects of IBMX were also measured and its IC50 values for PDE3, 4 and 5 were 6.5 +/- 1.2, 26.3 +/- 3.9 and 31.7 +/- 5.3 microm, respectively. KMUP-1 (0.01-10 microm) augmented intracellular cyclic AMP and cyclic GMP levels in guinea-pig cultured tracheal smooth muscle cells. These increases in cyclic AMP and cyclic GMP were abolished in the presence of an adenylate cyclase inhibitor SQ 22536 (100 microm) and an sGC inhibitor ODQ (10 microm), respectively. KMUP-1 (10 microm) increased the expression of protein kinase A (PKARI) and protein kinase G (PKG1alpha1beta) in a time-dependent manner, but this was only significant for PKG after 9 h. Intratracheal administration of tumour necrosis factor-alpha (TNF-alpha, 0.01 mg kg(-1)) induced bronchoconstriction and exhibited a time-dependent increase in lung resistance (RL) and decrease in dynamic lung compliance (Cdyn). KMUP-1 (1.0 mg kg(-1)), injected intravenously for 10 min before the intratracheal TNF-alpha, reversed these changes in RL and Cdyn. These data indicate that KMUP-1 activates sGC, produces relaxation that was partly dependent on an intact epithelium, inhibits PDEs and increases intracellular cyclic AMP and cyclic GMP, which then increases PKA and PKG, leading to the opening of K+ channels and resulting tracheal relaxation.


Assuntos
AMP Cíclico/fisiologia , GMP Cíclico/fisiologia , Piperidinas/farmacologia , Canais de Potássio/fisiologia , Mucosa Respiratória/fisiologia , Traqueia/efeitos dos fármacos , Vasodilatadores/farmacologia , Xantinas/farmacologia , Animais , Células Cultivadas , Proteínas Quinases Dependentes de AMP Cíclico/biossíntese , Proteínas Quinases Dependentes de GMP Cíclico/biossíntese , Relação Dose-Resposta a Droga , Guanilato Ciclase/antagonistas & inibidores , Cobaias , Técnicas In Vitro , Masculino , Relaxamento Muscular/efeitos dos fármacos , Músculo Liso/citologia , Músculo Liso/efeitos dos fármacos , Músculo Liso/fisiologia , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase/metabolismo , Inibidores de Fosfodiesterase/farmacologia , Testes de Função Respiratória , Traqueia/fisiologia
9.
Kaohsiung J Med Sci ; 19(12): 593-8, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14719556

RESUMO

Between May 1988 and July 2002, six patients with pneumonia due to diesel, animal, or vegetable oil aspiration were admitted to Kaohsiung Medical University Hospital. The purpose of this study was to demonstrate distinctive radiographic findings of oil-induced lipoid pneumonitis on initial serial chest roentgenograms and high-resolution computerized tomography (CT) scans. Initial chest roentgenograms (n = 6), CT scans (n = 6), and roentgenography and CT follow-up studies were analyzed retrospectively by two chest radiologists and two surgeons, focusing on the pattern and distribution of parenchymal abnormalities. The most common location was the right middle lobe, followed by the right lower lobe, the left lower lobe, and the lingular lobe. Follow-up chest roentgenograms (n = 6) showed complete disappearance of the parenchymal lesions in only one patient and partial decrease in the extent of lesions in five patients. Lipoid pneumonia presents non-specific findings on chest roentgenography. It is commonly located in both lower and the right middle lobes. On high-resolution CT, the lesions appear most commonly as areas of consolidation, ground-glass attenuation mixed with paving pattern, and poorly defined nodules.


Assuntos
Diagnóstico Diferencial , Pneumonia Lipoide/diagnóstico por imagem , Radiografia Torácica , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pneumonia Lipoide/patologia , Tomografia Computadorizada por Raios X
10.
Kaohsiung J Med Sci ; 18(6): 305-8, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12355931

RESUMO

A 21-year-old female patient with Marfan's syndrome suffering from chronic ascending aortic dissection and aortic insufficiency was treated with total aortic root replacement by Cabrol technique (or procedure). The post-operative course was smooth and the patient recovered satisfactorily with very stable hemodynamic condition and good appetite. Unfortunately she complained of sudden severe abdominal pain followed by complete anuria on the fifth post-operative day. The MRI demonstrated abdominal aortic dissection with malperfusion of all the abdominal organs. Rapid increase of aminotransferases (SGOT and SGPT), severe acidosis and rapid deterioration of vital signs within 10 hours discouraged us from trying surgical intervention. The puzzle of management in those cases will be discussed.


Assuntos
Aneurisma da Aorta Abdominal/terapia , Doenças da Aorta/cirurgia , Dissecção Aórtica/cirurgia , Síndrome de Marfan/complicações , Complicações Pós-Operatórias/terapia , Adulto , Insuficiência da Valva Aórtica/cirurgia , Dilatação Patológica/cirurgia , Feminino , Humanos , Stents
11.
J Cardiovasc Pharmacol ; 39(6): 803-13, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12021574

RESUMO

A propanolamine derivative with vanillylamide base, KMUP 880602, was first investigated under in vivo and in vitro conditions. IV KMUP 880602 (0.1, 0.5, 1.0, and 2.0 mg/kg) produced dose-dependent hypotensive and bradycardia responses in pentobarbital-anesthetized Wistar rats. KMUP 880602 also markedly inhibited both the tachycardia effects induced by (-)isoproterenol and arterial pressor responses induced by phenylephrine. In isolated guinea pig tissues, KMUP 880602 competitively antagonized (-)isoproterenol-induced positive inotropic and chronotropic effects of the atria and tracheal relaxation responses. The apparent pA2 values KMUP 880602 were 7.24 +/- 0.08 (right atria), 7.42 +/- 0.07 (left atria), and 6.24 +/- 0.06 (trachea). KMUP 880602 also produced a competitive antagonism of norepinephrine-induced contraction in the isolated rat aorta with pA2 values of 7.64 +/- 0.18. In the radioligand-binding assay, [3H]CGP-12177 binding to rat ventricle and lung tissues and [3H]prazosin binding to brain membranes were inhibited by KMUP 880602 with pKi values of 7.27, 6.08, and 8.25, respectively. In isolated rat thoracic aorta, the vasorelaxant effects of KMUP 880602 on phenylephrine-induced contractions were attenuated by pretreatment with tetraethylammonium (10-3 M) and charybdotoxin (10-7 M) but not by glibenclamide, 4-aminopyridine, and apamin. In conclusion, KMUP 880602 is an alpha/beta-adrenoceptor blocker, with selective beta1-adrenoceptor blocking and vascular smooth muscle relaxation activities. Particularly, the vasorelaxant effect of KMUP 880602 is partially mediated by the opening of charybdotoxin-sensitive K+ channel.


Assuntos
Antagonistas Adrenérgicos alfa/farmacologia , Antagonistas Adrenérgicos beta/farmacologia , Capsaicina/análogos & derivados , Propanolaminas/química , Propanolaminas/farmacologia , Ácido Vanílico/química , Ácido Vanílico/farmacologia , Vasodilatadores/farmacologia , Antagonistas Adrenérgicos alfa/química , Antagonistas Adrenérgicos beta/química , Animais , Capsaicina/química , Capsaicina/farmacologia , Relação Dose-Resposta a Droga , Feminino , Cobaias , Técnicas In Vitro , Masculino , Ratos , Ratos Wistar , Ácido Vanílico/análogos & derivados , Vasodilatadores/química
12.
Br J Pharmacol ; 135(5): 1159-66, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11877322

RESUMO

1. In isolated endothelium-intact or denuded rabbit corpus cavernosum preconstricted with phenylephrine, KMUP-1 (0.001 - 10 microM) caused a concentration-dependent relaxation. 2. This relaxation of KMUP-1 was attenuated by endothelium removed, high K(+) and pretreatments with a soluble guanylyl cyclase (sGC) inhibitor ODQ (1 microM), a NOS inhibitor L-NAME (100 microM), a K(+) channel blocker TEA (10 mM), a K(ATP) channel blocker glibenclamide (1 microM), a voltage-dependent K(+) channel blocker 4-AP (100 microM) and Ca(2+)-dependent K(+) channel blockers apamin (1 microM) and charybdotoxin (ChTX, 0.1 microM). 3. The relaxant responses of KMUP-1 (0.01, 0.05, 0.1 microM) together with a PDE inhibitor IBMX (0.5 microM) had additive actions on rabbit corpus cavernosum smooth muscle (CCSM). 4. KMUP-1 (0.01 - 10 microM) induced increase of intracellular cyclic GMP level in the primary cell culture of rabbit CCSM. This increase in cyclic GMP content was abolished in the presence of ODQ (10 microM). 5. Both KMUP-1 and sildenafil at 0.2, 0.4, 0.6 mg kg(-1) caused increases of intracavernous pressure (ICP) and duration of tumescene (DT) in a dose-dependent manner. These in vivo activities of ICP for sildenafil and KMUP-1 are consistent with those of in vitro effects of cyclic GMP. 6. KMUP-1 has the following merits: (1) inhibition of PDE or cyclic GMP breakdown, (2) stimulation of NO/sGC/cyclic GMP pathway, and (3) subsequent stimulation of K(+) channels, in rabbit CCSM. We suggest that these merits play prominent roles in KMUP-1-induced CCSM relaxation-associated increases of ICP and penile erection.


Assuntos
GMP Cíclico/metabolismo , Relaxamento Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Pênis/efeitos dos fármacos , Inibidores de Fosfodiesterase/farmacologia , Piperidinas/farmacologia , Canais de Potássio/metabolismo , Xantinas/farmacologia , Animais , Células Cultivadas , Inibidores Enzimáticos/farmacologia , Guanilato Ciclase/antagonistas & inibidores , Técnicas In Vitro , Masculino , Músculo Liso/metabolismo , Músculo Liso/fisiologia , Óxido Nítrico Sintase/antagonistas & inibidores , Ereção Peniana/efeitos dos fármacos , Pênis/metabolismo , Pênis/fisiologia , Diester Fosfórico Hidrolases/metabolismo , Piperazinas/farmacologia , Bloqueadores dos Canais de Potássio/farmacologia , Purinas , Coelhos , Citrato de Sildenafila , Sulfonas
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