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1.
Artigo em Espanhol | IBECS | ID: ibc-118744

RESUMO

Introducción. La morbimortalidad en los países desarrollados se relaciona con hábitos adquiridos en la adolescencia. El alcohol es la droga más consumida por los adolescentes españoles, planteando su uso abusivo un problema preocupante para la salud pública. Objetivo. Valorar el patrón de consumo de bebidas alcohólicas de los jóvenes estudiantes de 4.o de ESO de la ciudad de Gandía y las características que definen a esta población y al entorno en el que se realiza. Metodología. Se trata de un estudio descriptivo transversal del consumo de alcohol en los adolescentes de entre 15 y 18 años de Gandía, que se lleva a cabo mediante una encuesta con diferentes cuestiones relacionadas con los hábitos de salud de las cuales 9 se refieren al consumo de alcohol. Resultados. De los 346 encuestados, el 98% son menores de edad. El 93,3% ha probado alguna vez una bebida alcohólica, haciendo botellón habitualmente el 48,5% y habiéndose emborrachado alguna vez el 45,5%, concentrándose el consumo en el fin de semana. Un 76,6% tuvo el primer contacto con el alcohol en el entorno familiar. Conclusión. El consumo de alcohol en el adolescente es muy elevado, es un consumo mayoritariamente de fin de semana con una alta prevalencia en las intoxicaciones etílicas, consumo que se realiza en espacios públicos y con los amigos (AU)


Introduction: The morbidity and mortality in developed countries is related to habits acquired in adolescence. Alcohol is the drug most consumed by Spanish adolescents, making its abuse a concern for public health. Objective: To evaluate the pattern of alcohol consumption of 4 th year secondary school pupils in the city of Gandia, the defining characteristics of this population and the environment in which this takes place. Methodology: This is a descriptive study of alcohol use in adolescents aged 15 to 18 years of Gandia, which was carried out through a survey of different issues related to health habits, nine of which relate to consumption alcohol. Results: Of the 346 adolescents surveyed, 98% were minors, 93.3% had tried an alcoholic drink. Just under half (48.5%) took part in street binge-drinking, and 45.5% had got drunk at least once. Consumption was mainly during the weekend. More than three-quarters (76.6%) had their first contact with alcohol in the family. Conclusion: Alcohol use among adolescents is high, with consumption is mostly at weekends and with a high prevalence of alcohol intoxication, drinking in public places, and with friends (AU)


Assuntos
Humanos , Masculino , Feminino , Adolescente , Alcoolismo/epidemiologia , Alcoolismo/prevenção & controle , Comportamento do Adolescente , Comportamento do Adolescente/psicologia , Medicina do Adolescente/métodos , Medicina do Adolescente/organização & administração , Atenção Primária à Saúde/métodos , Serviços de Saúde do Adolescente/organização & administração , Serviços de Saúde do Adolescente/normas , Serviços de Saúde do Adolescente , Saúde do Adolescente , Estudos Transversais/métodos , Estudos Transversais/tendências , Indicadores de Morbimortalidade
2.
Semergen ; 40(1): 12-7, 2014.
Artigo em Espanhol | MEDLINE | ID: mdl-23810199

RESUMO

INTRODUCTION: The morbidity and mortality in developed countries is related to habits acquired in adolescence. Alcohol is the drug most consumed by Spanish adolescents, making its abuse a concern for public health. OBJECTIVE: To evaluate the pattern of alcohol consumption of 4th year secondary school pupils in the city of Gandia, the defining characteristics of this population and the environment in which this takes place. METHODOLOGY: This is a descriptive study of alcohol use in adolescents aged 15 to 18 years of Gandia, which was carried out through a survey of different issues related to health habits, nine of which relate to consumption alcohol. RESULTS: Of the 346 adolescents surveyed, 98% were minors, 93.3% had tried an alcoholic drink. Just under half (48.5%) took part in street binge-drinking, and 45.5% had got drunk at least once. Consumption was mainly during the weekend. More than three-quarters (76.6%) had their first contact with alcohol in the family. CONCLUSION: Alcohol use among adolescents is high, with consumption is mostly at weekends and with a high prevalence of alcohol intoxication, drinking in public places, and with friends.


Assuntos
Comportamento do Adolescente , Consumo de Bebidas Alcoólicas/epidemiologia , Intoxicação Alcoólica/epidemiologia , Adolescente , Coleta de Dados , Feminino , Humanos , Masculino , Prevalência , Espanha/epidemiologia
3.
Mini Rev Med Chem ; 5(2): 217-29, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15720291

RESUMO

Recent research developments in the field of NO-donor compounds have concerned conjugation of NO-donor moieties with antioxidant groups, NO-donor targeting, design of NO-donor hybrid drugs and of NO-delivery systems. These new approaches are illustrated and discussed through selected examples.


Assuntos
Doadores de Óxido Nítrico/farmacologia , Animais , Antioxidantes/química , Sistemas de Liberação de Medicamentos , Desenho de Fármacos , Humanos , Doadores de Óxido Nítrico/química
4.
Xenobiotica ; 34(4): 345-52, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15268979

RESUMO

1. The results of an in vitro study of the metabolism of benzofuroxan using either cytosolic or microsomal fractions obtained from rat liver are reported. 2. Benzofuroxan was incubated with an appropriate volume of cytosol or microsomal suspension; control incubations were performed without the beta-nicotinamide adenine dinucleotide phosphate-generating system or, alternatively, by using the subcellular fractions inactivated by heating. Incubation mixtures were analysed by high-performance liquid chromatography. Two principal metabolites (M1, M2) were identified in the cytosolic fraction only. The dependence of M2 formation on thiol cofactors, incubation time and protein concentration was examined. 3. The two metabolites were isolated and characterized by their 1H-, 13C-nuclear magnetic resonance, infrared and mass spectra. The structures of o-benzoquinonedioxime (2) and 2,3-diaminopleuozuc (3), were arranged to M1 and M2 respectively. The proposed structures were confirmed by the identity of the metabolites with authentic samples obtained by synthesis. X-ray analysis showed that the dioxime metabolite had an amphy configuration. 4. A metabolic scheme for the formation of the two products is proposed.


Assuntos
Benzoquinonas/metabolismo , Benzoxazóis/metabolismo , Citosol/metabolismo , Microssomos Hepáticos/metabolismo , Modelos Biológicos , Fenazinas/metabolismo , Animais , Células Cultivadas , Masculino , Modelos Químicos , Ratos , Ratos Wistar
5.
Farmaco ; 58(9): 677-81, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-13679160

RESUMO

A series of N-alkylamide derivatives of 4-amino-3-furoxancarboxylic acids 5a-11a and their oxidation products, the azo derivatives 5b-11b, were synthesised and studied for their vasodilating properties. All the products were able to release rat aorta strips precontracted with (-)noradrenaline. Azo derivatives proved to be 20-200 times more potent than the parent amines. The large variation of lipophilicity within the two series does not seem to influence significantly the activity. Experiments carried out in the presence of oxyhaemoglobin (HbO(2)) suggest the involvement of nitric oxide (NO*) in the vasodilation.


Assuntos
Compostos Azo/farmacologia , Oxidiazóis/farmacologia , Vasodilatadores/farmacologia , Animais , Aorta Torácica/efeitos dos fármacos , Aorta Torácica/fisiologia , Compostos Azo/síntese química , Técnicas In Vitro , Masculino , Contração Muscular/efeitos dos fármacos , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/fisiologia , Óxido Nítrico/metabolismo , Oxidiazóis/síntese química , Oxiemoglobinas/metabolismo , Ratos , Ratos Wistar , Relação Estrutura-Atividade , Vasodilatadores/síntese química
6.
Farmaco ; 56(10): 799-802, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11718274

RESUMO

Benzofuroxans are interesting compounds which display several biochemical and pharmacological properties. Recent studies from our laboratory demonstrate that they are reduced by ferrous salts at room temperature and that the principal reaction products are o-nitroanilines. This paper shows that simple benzofuroxan derivatives are also able to oxidise HbO2 2+ to methemoglobin (MetHb3+) (UV detection) and to form o-nitroanilines (HPLC detection). From a toxicological point of view this reaction is interesting, since it indicates that the blood is a site for metabolism of these compounds with consequent methemoglobinemia and formation of toxic compounds.


Assuntos
Compostos de Anilina/química , Benzoxazóis/química , Química Farmacêutica , Nitrocompostos/química , Oxiemoglobinas/química , Compostos de Anilina/síntese química , Compostos de Anilina/farmacologia , Benzoxazóis/síntese química , Benzoxazóis/farmacologia , Nitrocompostos/síntese química , Nitrocompostos/farmacologia
7.
J Med Chem ; 44(21): 3463-8, 2001 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-11585451

RESUMO

A new series of nonsteroidal antiinflammatory drugs (NSAIDs) obtained by linking ibuprofen to selected furoxan moieties and to related furazans were synthesized and tested for their antiinflammatory, antiaggregatory, and ulcerogenic properties. All the derivatives are endowed with antiinflammatory activity comparable to that of ibuprofen, but, unlike this drug, they display reduced acute gastrotoxicity. The masking of the ibuprofen-free carboxylic group seems to be principally at the basis of this reduced topical irritant action. The two furoxan derivatives 8 and 9 also trigger potent antiaggregatory effects, principally as a consequence of their NO-donor ability.


Assuntos
Anti-Inflamatórios não Esteroides/síntese química , Óxidos N-Cíclicos/síntese química , Ibuprofeno/análogos & derivados , Ibuprofeno/síntese química , Doadores de Óxido Nítrico/síntese química , Oxidiazóis/síntese química , Inibidores da Agregação Plaquetária/síntese química , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Anti-Inflamatórios não Esteroides/toxicidade , Carragenina , Óxidos N-Cíclicos/farmacologia , Óxidos N-Cíclicos/toxicidade , Edema/tratamento farmacológico , Mucosa Gástrica/efeitos dos fármacos , Humanos , Ibuprofeno/farmacologia , Técnicas In Vitro , Masculino , Doadores de Óxido Nítrico/farmacologia , Doadores de Óxido Nítrico/toxicidade , Oxidiazóis/farmacologia , Oxidiazóis/toxicidade , Úlcera Péptica/induzido quimicamente , Inibidores da Agregação Plaquetária/farmacologia , Inibidores da Agregação Plaquetária/toxicidade , Ratos , Ratos Wistar
9.
Pharm Res ; 18(7): 987-91, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11496959

RESUMO

PURPOSE: Model compounds containing NO-donor furoxan moieties at the 3-positioned basic lateral chain of 1, a 1,4-dihydropyridine related to nicardipine, were synthesized in order to study their vasodilating activity as well as their basic and lipophilic behaviour. METHODS: All the compounds were obtained by a modified Hantzsch approach. Potentiometry was used to determine pKa and lipophilicity descriptors. The furoxan 4-aryl-1,4-dihydropyridines were assessed for their ability to release nitrite, in the presence of a large excess of cysteine, by the Griess reaction. Vasodilating activity of the products in the absence and in the presence of ODQ, a well-known guanylate cyclase inhibitor, was evaluated on rat thoracic aorta. RESULTS: The compounds display low basicity values and for this reason their log Ds at physiological pH are identical to the log Ps of the neutral forms. Products 2, 3 display vasodilating action principally dependent on their Ca2+-antagonist properties, whereas 4 behaves as a well-balanced hybrid with mixed Ca2+-channel blocker and NO-dependent vasodilator activities. CONCLUSIONS. Nitrogen containing lateral chain at the 3-position of 1 is a suitable molecular region to be modified in order to obtain well-balanced furoxan NO-donor 1,4-DHPs. This manipulation produces a decrease in the basicity. General analysis of pKa and lipophilicity descriptors of these new DHPs suggest that molecular flexibility could influence both their basicity and log PI.


Assuntos
Bloqueadores dos Canais de Cálcio/síntese química , Di-Hidropiridinas/síntese química , Doadores de Óxido Nítrico/síntese química , Animais , Aorta Torácica/efeitos dos fármacos , Aorta Torácica/fisiologia , Bloqueadores dos Canais de Cálcio/química , Bloqueadores dos Canais de Cálcio/farmacologia , Di-Hidropiridinas/química , Di-Hidropiridinas/farmacologia , Relação Dose-Resposta a Droga , Nicardipino/química , Nicardipino/farmacologia , Óxido Nítrico/biossíntese , Doadores de Óxido Nítrico/química , Doadores de Óxido Nítrico/farmacologia , Ratos , Vasodilatação/efeitos dos fármacos , Vasodilatação/fisiologia
10.
Pharm Res ; 18(2): 157-65, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11405285

RESUMO

PURPOSE: To obtain new cardiovascular agents with mixed Ca2+-channel antagonistic and NO-donor properties, a series of "hybrid" 1,4-dihydropyridines (1,4-DHPs), bearing NO-donating furoxan moieties on the 3-positioned lateral ester chain were synthesized and pharmacologically characterized. Furazan analogues were also prepared and investigated for control purposes, because they are unable to release NO. METHODS: Synthesis of the models was achieved by a modified Hantzsch approach. All of the final furoxan 1,4-DHPs were assessed for their ability to produce nitrite in the presence of a large excess of cysteine by the Griess reaction. Vasodilating activity was evaluated on rat aorta and expressed as EC50 and EC50MB values, obtained in the absence and in the presence of methylene blue (MB) respectively, a well-known guanylate cyclase inhibitor. Affinities to 1,4-DHP receptor on Ca2+-channels, expressed as IC50 values, were determined through displacement experiments of [3H]-nitrendipine on rat cortex homogenates. RESULTS: Some hybrid compounds (derivatives 15a, 15b, 16a, and 16b) displayed vasodilating activity depending predominantly on their Ca2+-channel blocker properties. By contrast, some others (derivatives 17a, 17b, and 21) behaved as well-balanced hybrids with mixed Ca2+-channel blocking and NO-dependent vasodilating activities. CONCLUSION: This work demonstrates the possibility of obtaining well-balanced hybrids endowed with mixed NO-donor and Ca2+-channel blocker properties using appropriate 1,4-DHP and furoxan moieties. A procedure for the individual evaluation of the NO-dependent vasodilator component and that due to Ca2+-channel blocking is proposed.


Assuntos
Bloqueadores dos Canais de Cálcio/síntese química , Fármacos Cardiovasculares/síntese química , Di-Hidropiridinas/síntese química , Doadores de Óxido Nítrico/síntese química , Óxido Nítrico/metabolismo , Animais , Aorta/efeitos dos fármacos , Aorta/fisiologia , Bloqueadores dos Canais de Cálcio/química , Bloqueadores dos Canais de Cálcio/farmacologia , Fármacos Cardiovasculares/química , Fármacos Cardiovasculares/farmacologia , Di-Hidropiridinas/química , Di-Hidropiridinas/farmacologia , Relação Dose-Resposta a Droga , Masculino , Doadores de Óxido Nítrico/química , Doadores de Óxido Nítrico/farmacologia , Ratos , Ratos Wistar , Vasodilatação/efeitos dos fármacos , Vasodilatadores/síntese química , Vasodilatadores/química , Vasodilatadores/farmacologia
11.
Bioorg Med Chem Lett ; 11(3): 403-6, 2001 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-11212121

RESUMO

New anti-Helicobacter pylori (H. pylori) agents endowed with H2-antagonists properties were obtained by combining the lamtidine derived pharmacophoric group with the antibiotic calvatic acid. All the compounds were tested for their irreversible H2-antagonist properties and for their ability to inhibit 20 H. pylori strains, two of them metronidazole resistant. The most active derivative (compound 4) displayed antimicrobial activity similar to metronidazole.


Assuntos
Antibacterianos/síntese química , Helicobacter pylori/efeitos dos fármacos , Antagonistas dos Receptores H2 da Histamina/síntese química , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Benzoatos/química , Benzoatos/farmacologia , Ligação Competitiva , Técnicas de Química Combinatória , Relação Dose-Resposta a Droga , Resistência a Medicamentos , Cobaias , Átrios do Coração/química , Histamina/metabolismo , Antagonistas dos Receptores H2 da Histamina/farmacologia , Metronidazol/farmacologia , Testes de Sensibilidade Microbiana , Nitrilas/química , Nitrilas/farmacologia , Piperidinas/química , Piperidinas/farmacologia , Receptores Histamínicos H2/metabolismo , Relação Estrutura-Atividade , Triazóis/química , Triazóis/farmacologia
12.
Bioorg Med Chem ; 8(7): 1727-32, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10976520

RESUMO

The synthesis and in vitro vasodilating properties of hybrid compounds in which furoxan (1,2,5-oxadiazole 2-oxide) moieties, endowed with different NO-donor properties, were substituted for the nitroxy function of Nicorandil are reported. The corresponding cyanoguanidine analogues are also considered. This approach has led to a series of vasorelaxing compounds devoid of affinity for K(ATP) channels, whose activity is prevalently due to their ability to activate sGC, at the concentrations of the experiments. Related furazan (1,2,5-oxadiazole) derivatives, unable to release nitric oxide were also prepared and studied for control. The amide analogues of Nicorandil display feeble vasorelaxing action not involving the activation of K+ channels, while in the guanidine analogues, this mechanism seems to underlie this action.


Assuntos
Nicorandil/farmacologia , Oxidiazóis/farmacologia , Animais , Aorta Torácica/fisiologia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/fisiologia , Guanidinas/síntese química , Guanidinas/farmacologia , Concentração Inibidora 50 , Masculino , Contração Muscular/efeitos dos fármacos , Músculo Liso Vascular/efeitos dos fármacos , Nicorandil/análogos & derivados , Nicorandil/síntese química , Doadores de Óxido Nítrico/síntese química , Óxidos de Nitrogênio/metabolismo , Ressonância Magnética Nuclear Biomolecular , Oxidiazóis/síntese química , Canais de Potássio/efeitos dos fármacos , Cloreto de Potássio/farmacologia , Ratos , Ratos Wistar , Vasodilatação/efeitos dos fármacos , Vasodilatadores/síntese química , Vasodilatadores/farmacologia
13.
J Physiol Paris ; 94(1): 5-10, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10761682

RESUMO

In spite of the well recognized gastric antisecretory activity, the gastroprotective potential of histamine H2 receptor antagonists is controversial. Most clinical studies in fact indicate that these drugs do not substantially protect the gastric mucosa from aggressive factors. Nitric oxide (NO) has been recently recognized as a fundamental mediator in gastric defence mechanisms, due to its ability to increase gastric mucosal blood flow and mucus production and to inhibit neutrophils adherence to endothelial cells. The aim of this study was to investigate the gastroprotective and H2 receptor antagonistic activity of a series of lamtidine analogues which contain different NO-releasing moieties (furoxan, nitroxy and nitrosothiol). These compounds were tested, in comparison with related H2 antagonists devoid of NO-donor structures, in different H2 receptor assays and in the conscious rat against 0.6 N HCl-induced gastric lesions. All the compounds tested were able to antagonize histamine-mediated responses at cardiac and gastric H2 receptors; however, furoxan and nitroxy derivatives were 10-fold less potent than the analogues devoid of NO-donor properties. By contrast, NO-donor compounds were more active than reference H2 antagonists as gastroprotective agents against mucosal injury induced by 0.6 N HCl. Among the different NO-donor moieties, the furoxan group conferred to the H2 antagonist molecule the highest gastroprotective potential; this finding closely correlates with the characteristics of NO release. In conclusions, lamtidine-analogue H2 antagonists combined with NO-donor moieties are endowed with gastric antisecretory and protective activity and could be the prototypes of a new class of anti-ulcer drugs. Finally, the furoxan NO donor group seems to be the most favourable among the different moieties tested.


Assuntos
Ácido Gástrico/metabolismo , Antagonistas dos Receptores H2 da Histamina/farmacologia , Doadores de Óxido Nítrico/farmacologia , Estômago/efeitos dos fármacos , Animais , Mucosa Gástrica/metabolismo , Cobaias , Histamina/farmacologia , Ácido Clorídrico/farmacologia , Técnicas In Vitro , Masculino , Óxido Nítrico/metabolismo , Músculos Papilares/efeitos dos fármacos , Músculos Papilares/metabolismo , Ratos , Ratos Wistar , Estômago/patologia
14.
Pharmacol Res ; 41(4): 469-74, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10704272

RESUMO

A series of nitroso compounds gem -substituted with electron-withdrawing groups (R(2)C(X)NO, R=alkyl, X=NO(2), CN, Cl), were studied for their in vitro and in vivo vasodilating properties as well as for their ability to activate soluble guanylate cyclase (sGC) in RFL-6 cells. All the compounds, with the sole exception of chloro derivative, display good in vitro vasodilating action and are able to increase the basal level of cGMP. Their potencies as vasodilators decrease in the presence of oxyhaemoglobin, a scavenger of nitric oxide (NO). The haemodynamic profile of the most interesting compounds, assessed in anaesthetized pigs, is also in line with a release of NO from these compounds.


Assuntos
Compostos Nitrosos/farmacologia , Vasodilatadores/farmacologia , Potenciais de Ação/efeitos dos fármacos , Animais , Aorta Torácica/efeitos dos fármacos , Linhagem Celular , GMP Cíclico/metabolismo , Elétrons , Inibidores Enzimáticos/farmacologia , Guanilato Ciclase/antagonistas & inibidores , Hemodinâmica/efeitos dos fármacos , Técnicas In Vitro , Indicadores e Reagentes , Masculino , Doadores de Óxido Nítrico/farmacologia , Compostos Nitrosos/química , Ratos , Ratos Wistar , Suínos , Vasodilatadores/química
15.
Chirality ; 11(7): 602-8, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10423289

RESUMO

The chromatographic chiral resolution of racemic methyl 1, 4-dihydro-2,6-dimethyl-5-nitro-4-benzofurazanyl-3-carboxylates 1 and 2 and their benzofuroxanyl analogues 3 and 4 were studied on Whelk-O1, Chiralcel OD-H, Chiralcel OJ, and Chiralpak AD and AS. These CSPs were selected on the basis of the results of structural searches in Chirbase. Examination of the data and cluster analysis pointed out the influence of benzofurazane-benzofuroxane change versus alpha-beta connection change on retention and enantioselectivity, respectively. The major contribution to the retention change arose from the type of heterocycle, whereas the major contribution to the enantioselectivity change came from the mode of connection (alpha or beta) almost irrespective of the nature of the heterocycle. It resulted in a similarity of behaviour between 1 and 2 on one hand and 3 and 4 on the other as far as capacity factors were concerned, and in a similarity of behaviour between 1 and 3 on the one hand and 2 and 4 on the other as far as enantioselectivities were concerned. Chiralpak AS was selected for semipreparative resolution of the enantiomers. The study of several CSPs allowed us to obtain correlations of structure with retention and enantioselectivity as well as the choice of a semipreparative support to provide the quantities for biological tests. Copyright 1999 Wiley-Liss, Inc.

16.
Pharm Res ; 16(6): 956-60, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10397620

RESUMO

PURPOSE: To investigate the effect of benzofusion on NO donor properties and related biological activities of the furoxan system. The biological properties considered were the ability to increase the cytosolic levels of cGMP in C6 cells and vasodilation. METHODS: NO donor properties were investigated either in the presence or the absence of cysteine by using the Griess reaction, chemiluminescence, and gas chromatography. Increase of cytosolic cGMP levels were evaluated by radioimmunoassay. Vasodilating activity was assessed on rat aorta strips precontracted with noradrenaline, in the presence and the absence of oxyhemoglobin (HbO2) and methylene blue (MB), respectively. RESULTS: Benzofuroxan and its methyl and cyano derivatives were unable to release NO under the experimental conditions. Generally these compounds displayed feeble vasodilating properties and were able to weakly stimulate soluble guanylate cyclase (sGC). By contrast, benzodifuroxan and benzotrifuroxan were able to produce both NO* and its reduced form NO- , the nitroxyl anion. They displayed potent vasodilating properties and were able to increase cytosolic levels of cGMP in a concentration-dependent manner. CONCLUSIONS: The simple benzofuroxans considered here are devoid of the capability to release NO, they weakly stimulate sGC as well as manifest feeble vasodilating properties by a mechanism that does not involve a thiol-induced NO production. By contrast, benzodifuroxan and benzotrifuroxan behave as typical NO donor furoxans.


Assuntos
Benzoxazóis/farmacologia , GMP Cíclico/metabolismo , Doadores de Óxido Nítrico/farmacologia , Animais , Aorta , Benzoxazóis/síntese química , Benzoxazóis/química , Citosol/efeitos dos fármacos , Citosol/metabolismo , Relação Dose-Resposta a Droga , Guanilato Ciclase/metabolismo , Técnicas In Vitro , Masculino , Óxido Nítrico/metabolismo , Doadores de Óxido Nítrico/síntese química , Doadores de Óxido Nítrico/química , Norepinefrina/farmacologia , Ratos , Ratos Wistar , Relação Estrutura-Atividade , Células Tumorais Cultivadas , Vasodilatação/efeitos dos fármacos
17.
J Med Chem ; 42(8): 1422-7, 1999 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-10212128

RESUMO

Racemic methyl 1,4-dihydro-2, 6-dimethyl-5-nitro-4-(benzofurazanyl)pyridine-3-carboxylates (+/-)-10 and (+/-)-11 and their benzofuroxanyl analogues (+/-)-12 and (+/-)-13 were prepared using a modified Hantzsch reaction that involved the condensation of nitroacetone with methyl 3-aminocrotonate and the appropriate aldehydes. The racemic mixtures were resolved into the corresponding enantiomers. Whole-cell voltage-clamp studies on L-type Ca2+ channels expressed in a rat insulinoma cell line (RINm5F) showed that all the dextrorotatory antipodes were effective agonists of L-type Ca2+ currents, while the levorotatory ones were weak Ca2+ entry blockers. The (+)-enantiomer of benzofurazan-5'-yl derivative 11 demonstrated unusual activity in that, in addition to producing a potentiation of L-type currents, it interfered with the voltage-dependent gating of L-type channels by producing a net delay of their activation at low voltages. This compound represents an interesting tool to probe L-type Ca2+ channel structure and function.


Assuntos
Benzoxazóis/síntese química , Agonistas dos Canais de Cálcio/síntese química , Bloqueadores dos Canais de Cálcio/síntese química , Canais de Cálcio/efeitos dos fármacos , Piridinas/síntese química , Animais , Benzoxazóis/química , Benzoxazóis/farmacologia , Agonistas dos Canais de Cálcio/química , Agonistas dos Canais de Cálcio/farmacologia , Bloqueadores dos Canais de Cálcio/química , Bloqueadores dos Canais de Cálcio/farmacologia , Canais de Cálcio/fisiologia , Canais de Cálcio Tipo L , Ativação do Canal Iônico , Técnicas de Patch-Clamp , Piridinas/química , Piridinas/farmacologia , Ratos , Estereoisomerismo , Células Tumorais Cultivadas
18.
Br J Pharmacol ; 126(3): 639-48, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10188974

RESUMO

Previous studies show that linking acetylated glucosamine to S-nitroso-N-acetyl-D,L-penicillamine (SNAP) stabilizes the molecule and causes it to elicit unusually prolonged vasodilator effects in endothelium-denuded, isolated rat femoral arteries. Here we studied the propanoyl (SNPP; 3 carbon side-chain), valeryl (SNVP; 5C) and heptanoyl (SNHP; 7C) N-substituted analogues of SNAP (2C), to further investigate other molecular characteristics that might influence chemical stability and duration of vascular action of S-nitrosothiols. Spectrophotometric analysis revealed that SNVP was the most stable analogue in solution. Decomposition of all four compounds was accelerated by Cu(II) and cysteine, and neocuproine, a specific Cu(I) chelator, slowed decomposition of SNHP. Generation of NO from the compounds was confirmed by electrochemical detection at 37 degrees C. Bolus injections of SNAP (10 microl; 10(-8)-10(-3) M) into the perfusate of precontracted, isolated rat femoral arteries taken from adult male Wistar rats (400-500 g), caused concentration-dependent, transient vasodilatations irrespective of endothelial integrity. Equivalent vasodilatations induced by SNVP and SNHP were transient in endothelium-intact vessels but failed to recover to pre-injection pressures at moderate and high concentrations (10(-6)-10(-3) M) in those denuded of endothelium. This sustained effect (> 1 h) was most prevalent with SNHP and was largely reversed by the NO scavenger, haemoglobin. We suggest that increased lipophilicity of SNAP analogues with longer sidechains facilitates their retention by endothelium-denuded vessels; subsequent slow decomposition within the tissue generates sufficient NO to cause prolonged vasodilatation. This is a potentially useful characteristic for targeting NO delivery to areas of endothelial damage.


Assuntos
Penicilamina/análogos & derivados , 1-Octanol , Animais , Endotélio Vascular/fisiologia , Artéria Femoral/efeitos dos fármacos , Artéria Femoral/fisiologia , Concentração de Íons de Hidrogênio , Técnicas In Vitro , Masculino , Óxido Nítrico/metabolismo , Óxido Nítrico/fisiologia , Doadores de Óxido Nítrico/farmacologia , Penicilamina/química , Penicilamina/metabolismo , Penicilamina/farmacologia , Ratos , Ratos Wistar , Solubilidade , Vasodilatação/efeitos dos fármacos , Água
19.
Farmaco ; 53(7): 519-24, 1998 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-9836464

RESUMO

A series of analogues of prazosin, in which 1-methyl or 1-phenylpyrazole moieties were substituted for the furan ring, were synthesized and studied for their alpha 1-adrenoceptor antagonist activity. The role of the five member heterocyclic substructures in determining the affinity for the alpha 1-receptor is briefly discussed.


Assuntos
Antagonistas Adrenérgicos alfa/química , Antagonistas Adrenérgicos alfa/síntese química , Prazosina/análogos & derivados , Pirazóis/química , Pirazóis/síntese química , Antagonistas Adrenérgicos alfa/farmacologia , Animais , Modelos Moleculares , Músculo Liso Vascular/efeitos dos fármacos , Pirazóis/farmacologia , Ratos , Relação Estrutura-Atividade
20.
Pharm Res ; 15(9): 1407-13, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9755893

RESUMO

PURPOSE: The objective of this study was to compare and interpret the variations in lipophilicity of homologous (p-methylbenzyl)alkylamines (MBAAs) in isotropic (octanol/water) and anisotropic (zwitterionic liposomes/water) system. METHODS: Two experimental approaches were used, namely the pH-metric method to measure lipophilicity parameters in octanol/water and liposomes/water systems, and changes in NMR relaxation rates to validate the former method and to gain additional insights into the mechanisms of liposomes/water partitioning. RESULTS: For long-chain homologues (N-butyl to N-heptyl), the octanol/water and liposomes/water systems mostly expressed hydrophobicity. In contrast, the lipophilicity of the shorter homologues (N-methyl to N-propyl) in the two systems expressed various electrostatic and polar interactions. CONCLUSIONS: The study sheds light on the molecular interactions between zwitterionic liposomes and amphiphilic solutes in neutral and cationic form.


Assuntos
1-Octanol/química , Alcanos/química , Água/química , Portadores de Fármacos , Lipídeos/química , Lipossomos/química , Espectroscopia de Ressonância Magnética
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