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1.
Eur Rev Med Pharmacol Sci ; 23(16): 6858-6867, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31486485

RESUMEN

OBJECTIVE: This study aims to investigate the expression level of lncRNA ITGB1 both in bladder cancer (BCa) tissue and cell lines, as well as to evaluate its function and potential mechanism in the progression of BCa. PATIENTS AND METHODS: The expressions of lncRNA ITGB1 in 36 BCa tissues samples (and corresponding adjacent normal ones) and cell lines were detected by quantitative real-time polymerase chain reaction (qRT-PCR). After transfection of sh-ITGB1 in BCa cell lines, the effect of ITGB1 on the proliferation of BCa cells was examined by cell counting kit-8 (CCK-8) assay and colony formation assay. Subsequently, qRT-PCR was used to examine microRNA-10a expression in BCa tissues and cells after ITGB1 was silenced. At the same time, the correlation between ITGB1 and microRNA-10a expression was analyzed. Finally, cell recovery experiment was applied for the in-depth study of the interaction between ITGB1 and microRNA-10a and its underlying mechanism. RESULTS: LncRNA ITGB1 was found upregulated in BCa tissues and cell lines. Knockdown of lncRNA ITGB1 remarkably inhibited cell proliferation. The expression levels of ITGB1 and microRNA-10a in BCa tissues were negatively correlated. ITGB1 downregulation was found to be able to enhance microRNA-10a expression, suggesting that microRNA-10a may be a potential target for ITGB1 in BCa. In addition, cell reverse experiment also verified that ITGB1 could regulate the expression of microRNA-10a, and their interaction affected the malignant progression of BCa. CONCLUSIONS: LncRNA ITGB1 level is upregulated in BCa tissues and associated with the pathological stage of BCa, which could be used as a new predictor of BCa patients' prognosis. In addition, ITGB1 might promote BCa cell proliferation via regulating microRNA-10a expression.


Asunto(s)
Regulación Neoplásica de la Expresión Génica , Integrina beta1/genética , MicroARNs/genética , ARN Largo no Codificante/genética , Neoplasias de la Vejiga Urinaria/genética , Línea Celular Tumoral , Proliferación Celular/genética , Progresión de la Enfermedad , Humanos , Estimación de Kaplan-Meier , Transfección , Neoplasias de la Vejiga Urinaria/patología
2.
Respir Physiol Neurobiol ; 257: 100-106, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-29474953

RESUMEN

GABA, muscimol, and baclofen were microinjected into the rostral (rNTS) and caudal solitary tract nucleus (cNTS) in 24 anesthetized cats. Electromyograms (EMGs) of diaphragm (DIA) and abdominal muscles (ABD), blood pressure and esophageal pressure (EP) were recorded and analysed. Bilateral microinjections of 1 mM GABA (total 66 ±â€¯4 nl), 1 mM baclofen (64 ±â€¯4 nl) and unilateral microinjections of 0.5 mM muscimol (33 ±â€¯1 nl) in the rNTS significantly reduced cough number (CN), amplitudes of ABD EMGs, expiratory EP, and prolonged the duration of the cough inspiratory phase. GABA microinjections decreased the amplitudes of cough-related DIA EMGs and inspiratory EP; muscimol microinjections decreased the cough DIA EMG on the contralateral side. Only microinjections of GABA into the cNTS suppressed CN. In some cases, microinjections prolonged the inspiratory phase, lowered respiratory rate, changed the depth of breathing, and increased blood pressure and heart rate. Our results confirm that GABA-ergic inhibitory mechanisms in the rNTS can regulate coughing in the anesthetized cat.


Asunto(s)
Tos/metabolismo , Núcleo Solitario/metabolismo , Transmisión Sináptica/fisiología , Ácido gamma-Aminobutírico/metabolismo , Animales , Baclofeno/farmacología , Presión Sanguínea/efectos de los fármacos , Presión Sanguínea/fisiología , Gatos , Esófago/efectos de los fármacos , Esófago/metabolismo , Frecuencia Cardíaca/efectos de los fármacos , Frecuencia Cardíaca/fisiología , Inhalación/efectos de los fármacos , Inhalación/fisiología , Masculino , Muscimol/farmacología , Neurotransmisores/farmacología , Receptores de GABA-B/metabolismo , Núcleo Solitario/efectos de los fármacos , Transmisión Sináptica/efectos de los fármacos , Ácido gamma-Aminobutírico/farmacología
3.
Biochim Biophys Acta ; 674(1): 19-29, 1981 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-7236728

RESUMEN

Liposomes with synthetic saccharide determinants were prepared from synthetic cholesterol conjugates of D-mannose and 6-amino-6-deoxy-D-mannose and labeled with [51Cr]chromate. The kinetics and tissue distribution of label in mice were determined after footpad and subcutaneous injection. Liposomes bearing either of these saccharide determinants greatly increased retention of label at the injection sites compared to control liposomes, which contain no glycolipid, and to free [51Cr]chromate. Draining lymph nodes contained small fractions of the injected radioactivity but in some cases this retention was saccharide-dependent and highly concentrated. These results show that incorporation of synthetic glycolipids can substantially alter the in vivo lifetime and distribution of liposomes outside the bloodstream. Such surface-modified liposomes may be useful for sustained release or selective delivery of therapeutic or diagnostic agents.


Asunto(s)
Glucolípidos/metabolismo , Liposomas/metabolismo , Animales , Colesterol/administración & dosificación , Colesterol/análogos & derivados , Colesterol/metabolismo , Glucolípidos/administración & dosificación , Inyecciones , Liposomas/administración & dosificación , Ganglios Linfáticos/metabolismo , Masculino , Manósidos/administración & dosificación , Manósidos/metabolismo , Tasa de Depuración Metabólica , Ratones , Distribución Tisular
4.
J Med Chem ; 24(10): 1202-11, 1981 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-7328581

RESUMEN

The interaction of the nonsteroidal antiinflammatory drugs (NSAIDS) indomethacin, diflunisal, and flurbiprofen and the active sulfide metabolite of sulindac with phosphatidylcholine (PC) liposomes was investigated using differential scanning calorimetry (DSC). These biologically active structures decrease the phase transition temperature and broaden the transition peak with increasing concentration, but without affecting the enthalpy change for the transition on the thermal scan. A comparison with the effects of the prodrug sulindac and its inactive sulfone metabolite suggests that the main action of NSAIDS on membranes is a reduction of the cooperative interaction between phospholipid molecules. The probable positions of these compounds in the bilayer are inferred from similar DSC effects of several reference compounds whose mode of binding to the PC bilayer have previously been described. The active antiinflammatory structures appear to insert deeply into the hydrocarbon region of the bilayer, whereas the inactive compounds probably bind mainly to the carbonyl region near the surface. Using purple membrane as a model to study the drug effect on protein--protein interaction in this membrane system, low concentrations of active NSAIDS effectively dissociate the bacteriorhodopsin lattice. These results suggest that the active NSAIDS studied here are able to partition deeply into the hydrocarbon region of the bilayer and interact with a membrane protein imbedded inside the bilayer. The prodrug sulindac per se is devoid of any significant membrane effects.


Asunto(s)
Antiinflamatorios/metabolismo , Bacteriorodopsinas/metabolismo , Carotenoides/metabolismo , Liposomas/metabolismo , Humanos , Concentración de Iones de Hidrógeno , Membrana Dobles de Lípidos/metabolismo , Lípidos de la Membrana/metabolismo , Proteínas de la Membrana/metabolismo , Fosfatidilcolinas/metabolismo , Fosfolípidos/metabolismo , Relación Estructura-Actividad , Termodinámica
5.
J Med Chem ; 24(10): 1197-202, 1981 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-6276543

RESUMEN

High-resolution proton NMR and spin-label ESR spectroscopies have been applied to examine the interaction of the nonsteroidal antiinflammatory drug sulindac (1) and its active sulfide metabolite (2) and inactive sulfone metabolite (3) with phospholipid membranes. Only weak interactions were observed with 1 and 3, but a strong interaction with 2 was indicated both by specific changes in the proton transverse relaxation rate (1/T2) of different substituents in 2 and by a unique shift in membrane transition temperature in the presence of 2 as measured by the ESR technique. Since the structural differences of these compounds are confined to a single polar substituent, i.e., the oxidation state of the sulfur atom, the strong interaction of the sulfide metabolite (2) with the neutral phospholipid membrane is ascribed to its high partition coefficient in the lipid membrane and its ability to penetrate into the lipid bilayer with the carboxyl group remaining at the polar membrane surface. As evidenced from the ESR spectra of two spin-labels, C5- and C12-doxylstearic acid, no significant change of the membrane fluidity was induced by the interaction of 2 with phospholipid vesicles.


Asunto(s)
Indenos/metabolismo , Lípidos de la Membrana/metabolismo , Fosfolípidos/metabolismo , Sulindac/metabolismo , Espectroscopía de Resonancia por Spin del Electrón , Humanos , Espectroscopía de Resonancia Magnética , Fluidez de la Membrana/efectos de los fármacos , Sulindac/farmacología
6.
J Med Chem ; 20(9): 1146-52, 1977 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-411931

RESUMEN

Conformational analysis of indomethacin and other nonsteroidal antiinflammatory drugs leads to formulation of a hypothetical complementary receptor site model. The same model can serve to describe the prostaglandin cyclooxygenase active site, and, indeed, arachidonic and other polyunsaturated fatty acids could be folded on the model in a manner which rationalizes their stereospecific transformation to cyclic endo-peroxides (PGG). The model rationalizes the structure-activity relationships of enzyme substrates and inhibitors and appears to be in agreement with biochemical studies of the enzyme.


Asunto(s)
Acetatos/farmacología , Modelos Químicos , Prostaglandina-Endoperóxido Sintasas/metabolismo , Prostaglandinas/biosíntesis , Antiinflamatorios , Sitios de Unión , Inhibidores de la Ciclooxigenasa , Ácidos Grasos , Conformación Molecular , Relación Estructura-Actividad
7.
J Med Chem ; 23(11): 1184-8, 1980 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-7452668

RESUMEN

A group of 1-thio-beta-L-fucopyranosides containing hexadecane, 9-octadecene, adamantane, 1,2-diphenyltetrafluoroethane, and 3-hexynyl- and 3,6-dioxaoctylcholesterols were synthesized as potential immunologic adjuvants. Many of these fucosyl lipids and 6-(5-cholesten-3 beta-yloxy)hexyl 1 thioglycosides were found to give good response to subunit A/Victoria influenza virus. Carbohydrates with L-fucose and D-galactose backbones appeared essential for adjuvant activity. Lactose which has a terminal D-galactose moiety was found to be active, whereas L-arabinose which lacks a 5-(hydroxymethyl) group was inactive.


Asunto(s)
Adyuvantes Inmunológicos/síntesis química , Glucolípidos/síntesis química , Animales , Antígenos Virales , Fenómenos Químicos , Química , Femenino , Glucolípidos/farmacología , Virus de la Influenza A/inmunología , Ratones , Mitógenos , Factores de Tiempo
8.
J Med Chem ; 21(2): 221-5, 1978 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-621719

RESUMEN

Chemical modification of the 4'-N position of 1,4-diamino-1,4-dideoxy-3-O-(4-deoxy-4-propionamido-alpha-D-glucopyranosyl)-D-glucitol (GlA1) in the form of 4'-N-acyl analogues, e.g., 3, led to no significant potency enhancement. The n-propylamino analogue 4 was more active against gram-positive bacteria but was less act vs. gram-negative bacteria. The intrinsic activity of the 6'-chloro analogue 15 like the antibiotic GlA1 was not high, but the antibacterial spectrum was broad with moderate activity against most resistant organisms.


Asunto(s)
Antibacterianos/síntesis química , Aminoglicósidos/síntesis química , Aminoglicósidos/farmacología , Relación Estructura-Actividad
9.
J Med Chem ; 24(12): 1388-95, 1981 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7310815

RESUMEN

Various numbers of D-mannose residues have been attached via spacer arms to lysine, dilysine, and oligolysine backbones. These D-mannosyl peptide analogues were found to be potent competitive inhibitors of the uptake of 125I-labeled D-mannose-bovine serum albumin conjugate by rat alveolar macrophages. The inhibitory potency of these synthetic ligands increased with increasing number of carbohydrate moieties. The chirality of the peptide backbone did not appear to play a major role in binding, whereas variations of the length and linkage of the spacer arm notably affected the inhibitory activities. The saccharide specificity of the macrophage receptor was demonstrated by the inactivity of the corresponding D-galactosyl peptide analogues. The L-fucosyl peptide derivative was only weakly active. The trimannosyldilysine ligand (KI = 3.9 microM) and its analogues are potentially useful in selective delivery of therapeutic agents to macrophages.


Asunto(s)
Preparaciones Farmacéuticas/administración & dosificación , Animales , Fenómenos Químicos , Química , Femenino , Glicopéptidos/farmacología , Técnicas In Vitro , Ligandos , Macrófagos/efectos de los fármacos , Preparaciones Farmacéuticas/metabolismo , Ratas , Ratas Endogámicas
10.
J Med Chem ; 30(1): 136-42, 1987 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-3027330

RESUMEN

Kadsurenone, a specific receptor antagonist of platelet-activating factor (PAF), and its analogues were prepared from derivatives of cinnamyl alcohol and (allyloxy)phenol. Racemic kadsurenone, resolvable by a Chiralpak column at low temperatures, has an IC50 value of 2 X 10(-7) M, which is about 50% of the activity of the natural product (IC50 = 1 X 10(-7) M). The structural specificity of kadsurenone was further demonstrated by the low PAF-receptor-blocking activities of denudatin B, mirandin A, desallylkadsurenone, and the 2-epimer of kadsurenone.


Asunto(s)
Benzofuranos/síntesis química , Lignanos , Factor de Activación Plaquetaria/antagonistas & inhibidores , Glicoproteínas de Membrana Plaquetaria , Receptores de Superficie Celular/efectos de los fármacos , Receptores Acoplados a Proteínas G , Animales , Benzofuranos/farmacología , Plaquetas/metabolismo , Membrana Celular/metabolismo , Dicroismo Circular , Indicadores y Reactivos , Cinética , Espectroscopía de Resonancia Magnética , Conejos , Receptores de Superficie Celular/metabolismo , Relación Estructura-Actividad
11.
J Med Chem ; 21(11): 1158-62, 1978 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-102794

RESUMEN

Some 2-(substituted phenyl)oxazolo[4,5-b]pyridines and 2-(substituted phenyl)oxazolo[5,4-b]pyridines have good antiinflammatory and analgesic activity. A few possess activity comparable to phenylbutazone or indomethacin without producing the irritation in the gastrointestinal tract that acidic antiinflammatory compounds cause.


Asunto(s)
Antiinflamatorios/síntesis química , Piridinas/síntesis química , Animales , Antiinflamatorios no Esteroideos/síntesis química , Artritis Experimental/fisiopatología , Inhibidores de la Ciclooxigenasa , Edema/fisiopatología , Mucosa Gástrica/efectos de los fármacos , Dosificación Letal Mediana , Ratones , Piridinas/farmacología , Ratas , Relación Estructura-Actividad
12.
J Med Chem ; 21(11): 1100-4, 1978 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-309948

RESUMEN

We have made a series of 4- and 5-aryl- and 4- and 5-heteroarylsalicylic acid derivatives with the objective of reducing gastric irritation and increasing potency. Here we describe a series of 4- and 5-heterocyclic salicylic acids and their antiinflammatory-analgesic potencies measured in comparison to aspirin. An improvement of the therapeutic index over aspirin of 100 was achieved; however, the heterocyclic salicylic acids lacked antipyretic activity. Some physicochemical parameters which may bear on the antiinflammatory activity of these compounds are discussed.


Asunto(s)
Antiinflamatorios no Esteroideos/síntesis química , Salicilatos/síntesis química , Animales , Fenómenos Químicos , Química Física , Perros , Edema/fisiopatología , Hemorragia Gastrointestinal/inducido químicamente , Ratas , Salicilatos/farmacología
13.
J Med Chem ; 21(9): 965-78, 1978 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-309950

RESUMEN

In a study of nonsteroidal antiinflammatory and analgesic agents, a series of 1,3-dihydro-3-(substituted phenyl)imidazo[4,5-b]pyridin-2-ones-and 3-(substituted phenyl)triazolo[4,5-b]pyridines was prepared. Many of the imidazolones were alkylated on the free nitrogen. In a modified Randall-Selitto analgesic assay, the pain thresholds of both the inflamed and normal foot were elevated. This is not commonly observed with nonsteroidal antiinflammatory agents. The most active compounds were 1,3-dihydro-3[3,4-(methylenedioxy)phenyl]imidazo[4,5-b]pyridin-2-one (I-15) and its N-allyl (I-21) and N-isopropyl (I-121) derivatives. In the triazole series the 3-(2-fluoro- and 2,4-difluorophenyl)triazolo[4,5-b]pyridines (T-1 and T-8) were the best. The imidazole compounds were somewhat superior in analgesic activity to codeine and d-propoxyphene without showing any narcotic characteristics. Some of the compounds also possessed activity against carrageenan-induced foot edema in the rat, so these compounds represent a new class of nonnarcotic analgesic antiinflammatories, capable of producing a greater degree of analgesia than that obtainable with other nonsteroidal antiinflammatory agents.


Asunto(s)
Antiinflamatorios no Esteroideos/síntesis química , Piridinas/síntesis química , Piridonas/síntesis química , Animales , Femenino , Humanos , Inflamación/fisiopatología , Ratones , Naloxona/farmacología , Piridinas/farmacología , Piridonas/farmacología , Ratas , Tiempo de Reacción/efectos de los fármacos , Relación Estructura-Actividad , Síndrome de Abstinencia a Sustancias/inducido químicamente
14.
J Med Chem ; 21(9): 854-9, 1978 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-722752

RESUMEN

A number of alkyl, aryl, and aralkyl glycosides (mono- and disaccharides) substituted in the aglycon with a primary amino group have been found to exert insulin-like activity on rat adipocytes in vitro. Systematic variations in the saccharide configuration, glycosidic linkage, aglycon moiety, and sugar substitution pattern were investigated to delineate structure-activity relationships. A high degree of structural specificity was observed. Maximal insulin mimicking activity was obtained with the 6-aminohexyl 1-thio-D-mannopyranosides; the beta anomer was more active than the alpha anomer. Modification of the sugar hydroxyl groups resulted, in most cases, in partial or complete loss of biological activity at the levels tested; however, in a few instances, sugar-modified derivatives did show enhanced insulin-like effects. Specific structural types evaluated are discussed in greater detail. 6-Aminohexyl 1-thio-beta-D-mannopyramoside also exhibited in vivo insulin-like effects on both diaphragm muscle and omental adipose tissues. The specificities for the sugar as well as the aglycon portions of these carbohydrate derivatives suggest that both parts of the molecule are involved in the expression of the full biological activity observed; their respective roles in the mechanism of the insulin-like activity are discussed.


Asunto(s)
Glicósidos/síntesis química , Insulina , Tejido Adiposo/efectos de los fármacos , Tejido Adiposo/metabolismo , Animales , Femenino , Glucosa/metabolismo , Glucógeno/biosíntesis , Glicósidos/farmacología , Técnicas In Vitro , Insulina/farmacología , Lípidos/biosíntesis , Masculino , Conformación Molecular , Oxidación-Reducción , Ratas , Estereoisomerismo , Relación Estructura-Actividad
15.
J Med Chem ; 29(10): 1917-21, 1986 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-3020247

RESUMEN

The six (racemic or meso) isomers of 3,4-dimethyl-2,5-bis(3,4-dimethoxyphenyl)tetrahydrofuran and four corresponding desmethyl analogues were prepared and assayed as inhibitors of platelet activating factor (PAF) receptor binding to rabbit platelet plasma membranes. The inhibition by these isomers is stereodependent and varies with the gross shape of the molecules as determined by the molecular mechanics program MM2. The most potent PAF antagonist in this group of compounds is trans-2,5-bis(3,4,5-trimethoxyphenyl)tetrahydrofuran (L-652,731, 14) with an IC50 of 0.02 microM.


Asunto(s)
Furanos/farmacología , Extractos Vegetales/farmacología , Factor de Activación Plaquetaria/antagonistas & inhibidores , Animales , Furanos/síntesis química , Lignanos , Conformación Molecular , Extractos Vegetales/síntesis química , Conejos , Relación Estructura-Actividad
16.
J Med Chem ; 21(11): 1093-100, 1978 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-309947

RESUMEN

5-(2,4-Difluorophenyl)salicylic acid, diflunisal (25), is the best compound, in terms of both efficacy and safety, from over 500 salicylates investigated in our laboratories. It is a chemically distinct, nonacetylating salicylic acid, more active than aspirin as an analgesic and antiinflammatory agent and superior in duration of action and therapeutic index. Some recent clinical and biochemical observations are briefly discussed.


Asunto(s)
Antiinflamatorios no Esteroideos/síntesis química , Salicilatos/síntesis química , Animales , Fenómenos Químicos , Química , Perros , Ratas , Salicilatos/farmacología , Relación Estructura-Actividad
17.
J Med Chem ; 41(11): 1970-9, 1998 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-9599246

RESUMEN

By incorporating an N-hydroxyurea functionality onto diaryltetrahydrofurans, a novel series of compounds was investigated as dual 5-lipoxygenese (5-LO) inhibitor and platelet-activating factor (PAF) receptor antagonist. These dual functional compounds were evaluated in vitro for 5-LO inhibition in RBL cell extracts and human whole blood, and PAF receptor antagonism in a receptor binding assay. PAF-induced hemoconcentration and arachidonic acid- and TPA-induced ear edema in mice were used to determine in vivo activities. The structure-activity relationship analysis to define a preclinical lead is presented. (+/-)-trans-2-[3-methoxy-4-(4-chlorophenylthioethoxy)-5-(N-methyl- N-h ydroxyureidyl)methylphenyl]-5-(3,4, 5-trimethoxyphenyl)tetrahydrofuran (40, CMI-392) was selected for further study. In the arachidonic acid-induced mouse ear edema model, 40 was more potent than either zileuton (a 5-LO inhibitor) or BN 50739 (a PAF receptor antagonist), and it demonstrated the same inhibitory effect as a physical combination of the latter two agents. These results suggest that a single compound which both inhibits leukotriene synthesis and blocks PAF receptor binding may provide therapeutic advantages over single-acting agents. The clinical development of compound 40 is in progress.


Asunto(s)
Inhibidores Enzimáticos/farmacología , Furanos/farmacología , Inhibidores de la Lipooxigenasa , Glicoproteínas de Membrana Plaquetaria/antagonistas & inhibidores , Receptores de Superficie Celular , Receptores Acoplados a Proteínas G , Urea/análogos & derivados , Animales , Ácido Araquidónico/toxicidad , Plaquetas/efectos de los fármacos , Plaquetas/metabolismo , Plaquetas/ultraestructura , Células CHO , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Cricetinae , Evaluación Preclínica de Medicamentos , Edema/inducido químicamente , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/química , Furanos/síntesis química , Furanos/química , Hematócrito , Humanos , Leucotrieno B4/biosíntesis , Leucotrieno B4/sangre , Ratones , Ratas , Relación Estructura-Actividad , Acetato de Tetradecanoilforbol/toxicidad , Células Tumorales Cultivadas , Urea/síntesis química , Urea/química , Urea/farmacología
18.
Eur J Pharmacol ; 250(3): R13-4, 1993 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-8112391

RESUMEN

Epibatidine, an alkaloid isolated from skin of the poison frog, Epipedobates tricolor, has been shown to be a very potent analgesic with a non-opioid mechanism of action. We found that epibatidine was about 120 times more potent and has longer duration than nicotine in analgesia, which could be antagonized by pretreatment with mecamylamine. Furthermore, epibatidine competed with high affinity (IC50 = 70 pM, Ki = 43 pM) for [3H]cytisine binding in rat brain preparations. These results indicated that the analgesic activity of epibatidine is attributed to its unique property as the most potent nicotinic acetylcholine receptor agonist.


Asunto(s)
Analgésicos/farmacología , Encéfalo/metabolismo , Compuestos Bicíclicos Heterocíclicos con Puentes , Compuestos Bicíclicos con Puentes/farmacología , Piridinas/farmacología , Receptores Nicotínicos/efectos de los fármacos , Alcaloides/metabolismo , Analgésicos/metabolismo , Animales , Azocinas , Unión Competitiva , Encéfalo/efectos de los fármacos , Compuestos Bicíclicos con Puentes/metabolismo , Interacciones Farmacológicas , Mecamilamina/farmacología , Ratones , Nicotina/metabolismo , Nicotina/farmacología , Piridinas/metabolismo , Quinolizinas , Ratas , Receptores Nicotínicos/metabolismo
19.
Eur J Pharmacol ; 120(1): 33-41, 1986 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-3948914

RESUMEN

Platelet activating factor (PAF), a potent lipid-like vasoactive agent, induced rat foot edema when it was injected subplantarly. The edema reached its maximum 1 h after PAF challenge. Indomethacin did not inhibit the peak edematous response whereas both PAF antagonists, kadsurenone and L-652,731, inhibit the PAF-induced rat foot edema (PFE). Both PAF antagonists also partially block the first phase of the carrageenin-induced rat foot edema (CFE). Using the inhibition of [3H]PAF receptor binding to prepared rabbit platelet membranes, release of PAF or PAF-like materials in carrageenin-injected rat hindpaw was observed. These results suggest that the released PAF or PAF-like materials together with the released histamine and kinin evoke the first phase hindpaw edema in the rats. Indomethacin or PAF antagonist, administered alone, does not block the first phase or the second phase of CFE, respectively. However, PAF antagonist potentiated the inhibitory effects of indomethacin suggesting that the released PAF may also be involved in the biosynthesis of prostaglandins to initiate the second phase of rat CFE.


Asunto(s)
Benzofuranos , Edema/fisiopatología , Lignanos , Factor de Activación Plaquetaria/metabolismo , Animales , Antiinflamatorios/farmacología , Benzopiranos/farmacología , Carragenina , Masculino , Factor de Activación Plaquetaria/fisiología , Ratas , Ratas Endogámicas , Factores de Tiempo
20.
Thromb Res ; 34(6): 519-31, 1984 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-6429890

RESUMEN

The inhibitory effects of several antiinflammatory agents on the specific binding of tritiated 1-O-alkyl-2-O-acetyl-sn-glycero-3-phosphorylcholine, (platelet activating factor, PAF), with its receptor on isolated rabbit platelet plasma membranes were investigated. Several potent cyclooxygenase inhibitors do not inhibit 3H-PAF binding to its receptor sites. Yet, three others, indomethacin, phenylbutazone and sulfinpyrazone, as well as three non-cyclooxygenase inhibitors, the 3',4'-dimethoxy analog of indomethacin, the prodrug sulindac and its sulfone metabolite, are moderately active at relatively high concentrations (50 - 100 microM). Parallel inhibitions of 3H-PAF binding and PAF-induced platelet aggregation by derivatives of these antiinflammatory agents suggest that these inhibitors are probably interacting with the functional binding sites of PAF. The results clearly indicate that the configuration of PAF binding site is very different from the inhibitory site of cyclooxygenase. A preference for oxygenated substituents in these hydrophobic molecules to inhibit the PAF-receptor binding is noted. Some binding characteristics of the receptor are briefly discussed.


Asunto(s)
Antiinflamatorios/farmacología , Plaquetas/metabolismo , Factor de Activación Plaquetaria/fisiología , Animales , Sitios de Unión/efectos de los fármacos , Membrana Celular/metabolismo , Inhibidores de la Ciclooxigenasa , Indometacina/análogos & derivados , Indometacina/farmacología , Conejos
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