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1.
Public Health ; 199: 17-19, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34517289

RESUMEN

OBJECTIVES: This study aimed to determine SARS-CoV-2 seroprevalence among pregnant women in the Scottish population during the second wave of the COVID-19 pandemic. STUDY DESIGN: Prospective national serosurvey. METHODS: We tested 13,428 residual samples retrieved from pregnant women participating in the first trimester combined ultrasound and biochemical screening for fetal trisomy across Scotland for SARS-CoV-2 antibodies over a 6-month period from November 2020 to April 2021. Seroprevalence estimates were adjusted for the sensitivity and specificity of the assays and weighted to reference populations. RESULTS: Seroprevalence rates in the antenatal samples significantly increased from 5.5% (95% confidence interval [CI] 4.7%-6.5%) in the 5-week period up to and including International Organization for Standardization (ISO) Week 51 (w/b Monday 14 December 2020) to 11.3% (95% CI 10.1%-12.6%) in the 5-week period up to and including ISO Week 14 (w/b Monday 5 April 2021). Increasing seroprevalence trends across the second wave were observed among all age groups. CONCLUSIONS: By the end of the second wave of the COVID-19 pandemic, approximately one in 10 women tested around the end of the first trimester of pregnancy had antibodies to SARS-CoV-2, suggesting that the vast majority were still susceptible to COVID-19 as they progressed to the later stages of pregnancy, when risks from infection are elevated for both mother and baby.


Asunto(s)
COVID-19 , SARS-CoV-2 , Anticuerpos Antivirales , Femenino , Humanos , Inmunoglobulina G , Pandemias , Embarazo , Mujeres Embarazadas , Prevalencia , Estudios Prospectivos , Escocia/epidemiología , Estudios Seroepidemiológicos
2.
Neurosignals ; 18(1): 32-42, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20389133

RESUMEN

Rat pheochromocytoma (PC12) cells characteristically undergo differentiation when cultured with nerve growth factor (NGF). Here we show that NGF dramatically increased the adenylyl cyclase-activating property of forskolin in PC12 cells. This effect of NGF was well maintained even when NGF was removed after 4 days, even though the morphological features of neuronal differentiation were rapidly lost on removal of NGF. The enhanced cAMP production in response to forskolin could be due to a synergistic interaction between forskolin and endogenously released agonists acting on G(s)-coupled receptors. However, responses to forskolin were not attenuated by antagonists of adenosine A2 receptors or pituitary adenylate cyclase-activating polypeptide (PACAP) receptors, suggesting that adenosine and PACAP were not involved. Adenylyl cyclases 3, 6 and 9 were the predominant isoforms expressed in PC12 cells, but we found no evidence for NGF-induced changes in expression levels of any of the 9 adenylyl cyclase isoforms, nor in the expression of Gα(s). These findings highlight that NGF has a subtle influence on adenylyl cyclase activity in PC12 cells which may influence more than the neurite extension process classically associated with neuronal differentiation.


Asunto(s)
Adenilil Ciclasas/metabolismo , Diferenciación Celular/efectos de los fármacos , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Factor de Crecimiento Nervioso/farmacología , Análisis de Varianza , Animales , Recuento de Células/métodos , Colforsina/farmacología , AMP Cíclico/metabolismo , Interacciones Farmacológicas , Células PC12/efectos de los fármacos , Células PC12/fisiología , Polipéptido Hipofisario Activador de la Adenilato-Ciclasa/farmacología , Isoformas de Proteínas/metabolismo , Ratas , Factores de Tiempo , Tritio/metabolismo
3.
Br J Pharmacol ; 149(1): 110-20, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16880763

RESUMEN

BACKGROUND AND PURPOSE: The current study examined the utility of the recently described prostacyclin (prostanoid IP) receptor antagonist RO1138452 (2-(4-(4-isopropoxybenzyl)-phenylamino) imidazoline) as a tool for classifying prostanoid receptors. EXPERIMENTAL APPROACH: pA(2) values were determined on isolated smooth muscle and platelet preparations. KEY RESULTS: RO1138452 antagonized relaxation of human pulmonary artery, guinea-pig aorta and rabbit mesenteric artery induced by the selective IP agonist cicaprost. Schild plots had slopes close to unity, generating pA(2) values of 8.20, 8.39 and 8.12 respectively. Non-surmountable antagonism was sometimes found with the higher concentrations of RO1138452, attributable to the EP(3) contractile action of cicaprost. RO1138452 did not block relaxation of guinea-pig trachea induced by the EP(2)-selective agonist butaprost. In contrast, there was a modest inhibition of butaprost-induced relaxation of human pulmonary artery by RO1138452, implying activation of both EP(2) and IP receptors by butaprost. RO1138452 did not affect relaxation induced by PGE(2) (EP(4) agonist) and substance P (NK(1)/endothelium-dependent agonist) in rabbit mesenteric artery. In human and rat platelet-rich plasmas, RO1138452 antagonized cicaprost-induced inhibition of platelet aggregation in a surmountable manner; pA(2) values may have been affected by binding of RO1138452 to plasma protein. RO1138452 did not affect the inhibitory actions of PGD(2) (DP(1) agonist) and NECA (adenosine A(2A) agonist) in human platelets. CONCLUSIONS AND IMPLICATIONS: The data indicate that RO1138452 is a potent and selective IP receptor antagonist. RO1138452 represents an important addition to our armoury of prostanoid receptor antagonists and a potential clinical agent in situations where prostacyclin has a pathophysiological function.


Asunto(s)
Compuestos de Bencilo/farmacología , Plaquetas/efectos de los fármacos , Imidazoles/farmacología , Músculo Liso Vascular/efectos de los fármacos , Receptores de Epoprostenol/antagonistas & inhibidores , Alprostadil/análogos & derivados , Alprostadil/farmacología , Animales , Dinoprostona/farmacología , Endotelio Vascular/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Cobayas , Humanos , Técnicas In Vitro , Masculino , NG-Nitroarginina Metil Éster/farmacología , Unión Proteica , Conejos , Sustancia P/farmacología
4.
Sci Total Environ ; 360(1-3): 60-7, 2006 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-16597461

RESUMEN

There is strong epidemiological evidence of association between PM10 (particulate matter with an aerodynamic diameter less than or equal to 10 microm) and adverse health outcomes including death and increased hospital admissions for cardiopulmonary conditions. Ambient PM10 surrogates such as diesel exhaust particles (DEP), a common component of UK PM10 have been shown to induce lung inflammation in both humans and rodents. To date, few studies have reported on the toxicological response of UK PM10 in experimental animals. This study examines the pulmonary toxicological responses in male Sprague Dawley rats following the intratracheal instillation of Cardiff urban PM10. A mild but significant change in lung permeability was observed in the lung post-instillation of a high (10 mg) dose of the whole PM10 as adjudged by increases in lung to body weight ratio and total acellular lavage protein. Such effects were less marked following instillation of a water-soluble fraction (80% of the total mass) but histological examination showed that lung capillaries were swollen in size with this treatment. In conclusion, conventional toxicological, histological and toxicogenomic studies have indicated that Cardiff PM10 exhibits low bioreactivity in the form of mild permeability changes. Differential gene expression was observed when the lung was treated with whole PM10, containing durable particles, in comparison with the water-soluble fraction of PM10 that was devoid of particles. Such changes were linked to different histopathological events within the lung.


Asunto(s)
Contaminantes Atmosféricos/toxicidad , Polvo , Regulación de la Expresión Génica/efectos de los fármacos , Pulmón/efectos de los fármacos , Animales , Líquido del Lavado Bronquioalveolar/química , Perfilación de la Expresión Génica , Pulmón/metabolismo , Masculino , Análisis por Micromatrices , Tamaño de la Partícula , Ratas , Ratas Sprague-Dawley , Toxicogenética , Reino Unido
5.
J Clin Oncol ; 8(5): 881-5, 1990 May.
Artículo en Inglés | MEDLINE | ID: mdl-2332772

RESUMEN

Interferon-beta-serine (IFN-beta-ser) is a muteine, recombinant IFN that is tolerated at a dose fivefold to 10-fold higher than IFN-alfa and interacts with the same cell membrane receptor as IFN-alfa. We hypothesized that at high doses IFN-beta-ser might induce a higher response rate than IFN-alfa in metastatic renal cell carcinoma. We undertook a phase II trial of IFN-beta-ser in patients with metastatic renal cell carcinoma. Patients were treated three times each week by a 2-hour intravenous infusion. Doses were escalated weekly (.25 to 5.5 mg, 1 mg = 180,000,000 U) until the maximum-tolerated treatment dose (MTTD) was determined. The MTTD is defined as one dose level less than that which caused grade 3 toxicity and was subsequently administered three times weekly for at least 4 weeks. Twenty-nine patients were entered, and 25 were assessable for response and toxicity. The performance status was 0-1 in all patients and only one patient received previous chemotherapy. The MTTD dose was 2.5 mg (range, 0.5 to 5.5 mg per treatment), although in 10 patients, doses were later deescalated because of cumulative toxicity. Initial dose-limiting toxicity and cumulative toxicity were fatigue, malaise, and fever in most patients. Hepatic transaminitis, neutropenia, and elevation of serum creatinine were also observed but were not dose-limiting. There was one complete response (CR) and four partial responses (PRs). All responses but one occurred in pulmonary metastases. The median time to response was 26 days (range, 17 to 102 days). These data demonstrate that IFN-beta-ser given in high doses exhibits significant antitumor activity in renal cell carcinoma; however, the objective response rate is 20%. This is no higher than previous IFN studies; therefore, we reject the hypothesis than IFN-beta-ser at high doses may induce a greater response rate than IFN-alfa. However, we did observe more responses than were seen in a similar trial undertaken with lower dose IFN-beta serine in renal cell carcinoma.


Asunto(s)
Antineoplásicos/uso terapéutico , Carcinoma de Células Renales/terapia , Interferón Tipo I/uso terapéutico , Interferón beta , Neoplasias Renales/terapia , Adulto , Anciano , Antineoplásicos/administración & dosificación , Antineoplásicos/efectos adversos , Neoplasias Óseas/secundario , Neoplasias Óseas/terapia , Carcinoma de Células Renales/secundario , Evaluación de Medicamentos , Fatiga/etiología , Femenino , Fiebre/etiología , Humanos , Interferón Tipo I/administración & dosificación , Interferón Tipo I/efectos adversos , Interferón beta-1a , Interferon beta-1b , Neoplasias Renales/patología , Neoplasias Pulmonares/secundario , Neoplasias Pulmonares/terapia , Masculino , Persona de Mediana Edad , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/efectos adversos , Proteínas Recombinantes/uso terapéutico , Inducción de Remisión
6.
Trends Pharmacol Sci ; 17(1): 17-21, 1996 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8789354

RESUMEN

Prostacyclin (PGI2) has been traditionally regarded as an important regulator of haemostasis, mediating its effects through prostacyclin (IP) receptors coupled to adenylate cyclase. Recent evidence suggests, however, that IP receptor agonists can activate multiple signalling pathways via the same IP receptor. Moreover, IP receptor agonists have interesting actions outside of the cardiovascular system, even extending to the release of non-adrenergic non-cholinergic (NANC) transmitters from enteric neurones. Here, Helen Wise and Robert Jones highlight some of this new information on PGI2 and its receptors, describe the properties of some chemically novel PGI2 mimetics, and report on current therapeutic uses of PGI2.


Asunto(s)
Epoprostenol/farmacología , Epoprostenol/fisiología , Receptores de Prostaglandina/agonistas , Animales , Humanos , Receptores de Epoprostenol , Receptores de Prostaglandina/fisiología
7.
Cell Signal ; 9(7): 531-7, 1997 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9419817

RESUMEN

The role of cAMP in mediating prostaglandin E2 (PGE2)-stimulated aggregation of neutrophil-like HL-60 cells has been investigated. Although the EP2 receptors appear to couple to Gs-proteins, PGE2 stimulated HL-60 cell aggregation appears to be a cAMP-independent process. This response to PGE2 in independent of calcium and tyrosine kinase activity, appears to involve activation of phosphatidylinositol 3-kinase which is negatively regulated by phosphatidic acid generated from phospholipase D activity, and is partially dependent on protein kinase C activity. In contrast, although the chemotactic peptide N-formyl-methionyl-leucyl-phenylalanine (FMLP) produces a similar aggregation response to PGE2, FMLP uses a distinct intracellular signalling pathway. The aggregation response to FMLP involves activation of Gi-proteins, is partially dependent on extracellular calcium, is negatively regulated by protein kinase C, and is independent of phosphatidylinositol 3-kinase, phospholipase D and tyrosine kinase activity. The possibility exists that EP2 receptor activation leads to Gs-dependent, but cAMP-independent, stimulation of phosphatidylinositol 3-kinase activity in HL-60 cells.


Asunto(s)
AMP Cíclico/metabolismo , Dinoprostona/farmacología , Células HL-60/efectos de los fármacos , Agregación Celular/efectos de los fármacos , Células HL-60/citología , Humanos , Neutrófilos , Fosfatidilinositol 3-Quinasas/metabolismo , Fosfolipasa D/metabolismo , Proteína Quinasa C/metabolismo , Transducción de Señal
8.
Cell Signal ; 13(11): 841-7, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11583920

RESUMEN

Octimibate and related nonprostanoid prostacyclin mimetics are partial agonists displaying highly tissue-specific responses. Octimibate demonstrated considerably greater efficacy for stimulation of adenylyl cyclase activity in Chinese hamster ovary cells transiently expressing mouse prostacyclin receptors (mIP-CHO cells) when compared to human SK-N-SH neuroblastoma cells, which endogenously express prostacyclin (IP) receptors. Pretreatment of both cell types with pertussis toxin (PTx) failed to influence IP agonist efficacy or potency, indicating a lack of involvement of an agonist-stimulated inhibitory G(i)-coupled pathway. Although stimulation of mIP-CHO cells with the full agonist cicaprost increased both [3H]cyclic AMP and [3H]inositol phosphate ([3H]IP) accumulation (pEC(50) values of 8.35 and 6.82, respectively), IP receptor signalling through G(q) in SK-N-SH cells was absent. Inhibition of protein kinase C (PKC) in mIP-CHO cells increased [3H]IP accumulation but had no effect on [3H]cyclic AMP accumulation. Therefore, the poor coupling of the IP receptor in SK-N-SH cells to G(q) is unlikely to explain the relatively low efficacy of octimibate for stimulating adenylyl cyclase in these cells. Furthermore, protein kinase A (PKA) inhibition appears to enhance IP receptor signalling through both G(s) and G(q) in mIP-CHO cells.


Asunto(s)
Epoprostenol/análogos & derivados , Receptores de Prostaglandina/agonistas , Acetatos/farmacología , Toxina de Adenilato Ciclasa , Animales , Células CHO , Cricetinae , AMP Cíclico/biosíntesis , Relación Dosis-Respuesta a Droga , Epoprostenol/farmacología , Proteínas de Unión al GTP Heterotriméricas/metabolismo , Humanos , Imidazoles/farmacología , Oxazoles/farmacología , Toxina del Pertussis , Fenoxiacetatos/farmacología , Receptores de Epoprostenol , Receptores de Prostaglandina/metabolismo , Transducción de Señal , Células Tumorales Cultivadas , Fosfolipasas de Tipo C/metabolismo , Factores de Virulencia de Bordetella/farmacología
9.
J Leukoc Biol ; 60(4): 480-6, 1996 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8864132

RESUMEN

Rat peritoneal neutrophils stimulated by N-formyl-methionyl-leucyl-phenylalanine (fMLP) produce an aggregation response that can be inhibited by prostaglandin E2 (PGE2) with an IC50 value of 2.6 x 10(-9) M. Although PGE2 can stimulate [3H]cAMP production in neutrophils (EC50 4.3 x 10(-8) M), the anti-aggregation response cannot be significantly attenuated by inhibitors of adenylate cyclase or protein kinase A, neither can it be potentiated by inhibition of phosphodiesterase activity. Despite these observations, it still remains possible that PGE2-mediated inhibition of rat neutrophil aggregation is a cAMP-dependent response mediated by highly localized changes in neutrophil cAMP. The inhibitory effect of PGE2 does not appear to depend on effects on intracellular calcium or K(ATP) channels. Similarities exist between PGE2 and the profile of activity of phosphatidylinositol 3-kinase (PI 3-kinase) inhibitors, suggesting that PI 3-kinase is a possible target for PGE2 action in rat neutrophils.


Asunto(s)
Agregación Celular/efectos de los fármacos , Dinoprostona/farmacología , Neutrófilos/efectos de los fármacos , Sulfonamidas , Adenina/análogos & derivados , Adenina/farmacología , Androstadienos/farmacología , Animales , Líquido Ascítico/citología , Células Cultivadas , Quimiotaxis de Leucocito/efectos de los fármacos , AMP Cíclico/fisiología , Proteínas Quinasas Dependientes de AMP Cíclico/antagonistas & inhibidores , Inhibidores Enzimáticos/farmacología , Gliburida/farmacología , Isoquinolinas/farmacología , Masculino , N-Formilmetionina Leucil-Fenilalanina/farmacología , Fosfatidilinositol 3-Quinasas , Inhibidores de Fosfodiesterasa/farmacología , Fosfotransferasas (Aceptor de Grupo Alcohol)/antagonistas & inhibidores , Canales de Potasio/efectos de los fármacos , Pirrolidinonas/farmacología , Ratas , Ratas Sprague-Dawley , Rolipram , Wortmanina
10.
Br J Pharmacol ; 113(2): 581-7, 1994 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-7834211

RESUMEN

1. The effects of various prostanoid agonists have been compared on the increase in intracellular free calcium ([Ca2+]i) and the aggregation reaction of rat peritoneal neutrophils induced by N-formyl-L-methionyl-L-leucyl-L-phenylalanine (FMLP). 2. Prostaglandin E2 (PGE2) and the specific IP-receptor agonist, cicaprost, both inhibited the FMLP-induced increase in [Ca2+]i (IC50 33 nM and 18 nM respectively) and the FMLP-induced aggregation reaction (IC50 5.6 nM and 7.9 nM respectively). PGD2, PGF2 alpha, and the TP-receptor agonist, U 46619, were inactive at the highest concentration tested (1 microM). 3. The EP1-receptor agonist, 17-phenyl-omega-trinor PGE2, and the EP3-receptor agonists, GR 63799X and sulprostone, had no inhibitory effect on FMLP-stimulated rat neutrophils. 4. PGE1 (EP/IP-receptor agonist) and iloprost (IP-receptor agonist) inhibited the FMLP-induced increase in [Ca2+]i with IC50 values of 34 nM and 38 nM respectively. The EP2-receptor agonists, butaprost and misoprostol (1 microM), inhibited both FMLP-stimulated [Ca2+]i and aggregation. However another EP2-receptor agonist, AH 13205, was inactive in both assays. 5. Prostanoid receptors present on rat neutrophils were further characterized by measuring [3H]-adenosine 3':5'-cyclic monophosphate ([3H]-cyclic AMP) accumulation. Only those agonists capable of stimulating [3H]-cyclic AMP accumulation were able to inhibit both FMLP-stimulated [Ca2+]i and aggregation. 6. These results indicate that rat neutrophils possess inhibitory IP and EP-receptors; the relative potencies of PGE2, misoprostol and butaprost are those expected for the EP2-receptor subtype. No evidence for DP, FP, TP or EP1 and EP3-receptors was obtained.


Asunto(s)
Neutrófilos/efectos de los fármacos , Receptores de Prostaglandina/efectos de los fármacos , Animales , Calcio/metabolismo , Agregación Celular/efectos de los fármacos , AMP Cíclico/biosíntesis , Técnicas In Vitro , Masculino , N-Formilmetionina Leucil-Fenilalanina , Neutrófilos/metabolismo , Antagonistas de Prostaglandina/farmacología , Prostaglandinas Sintéticas/farmacología , Ratas , Ratas Sprague-Dawley , Receptores de Prostaglandina/agonistas , Receptores de Prostaglandina/antagonistas & inhibidores
11.
Br J Pharmacol ; 134(7): 1375-84, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11724742

RESUMEN

1. Chinese hamster ovary (CHO) cells were transiently transfected with the mouse prostacyclin (mIP) receptor to examine IP agonist-mediated stimulation of [(3)H]-cyclic AMP and [(3)H]-inositol phosphate production. 2. The prostacyclin analogues, cicaprost, iloprost, carbacyclin and prostaglandin E(1), stimulated adenylyl cyclase activity with EC(50) values of 5, 6, 25 and 95 nM, respectively. These IP agonists also stimulated the phospholipase C pathway with 10 - 40 fold lower potency than stimulation of adenylyl cyclase. 3. The non-prostanoid prostacyclin mimetics, octimibate, BMY 42393 and BMY 45778, also stimulated adenylyl cyclase activity, with EC(50) values of 219, 166 and 398 nM, respectively, but failed to stimulate [(3)H]-inositol phosphate production. 4. Octimibate, BMY 42393 and BMY 45778 inhibited iloprost-stimulated [(3)H]-inositol phosphate production in a non-competitive manner. 5. Activation of the endogenously-expressed P(2) purinergic receptor by ATP led to an increase in [(3)H]-inositol phosphate production which was inhibited by the non-prostanoid prostacyclin mimetics in non-transfected CHO cells. Prostacyclin analogues and other prostanoid receptor ligands failed to inhibit ATP-stimulated [(3)H]-inositol phosphate production. 6. A comparison between the IP receptor-specific non-prostanoid ONO-1310 and the structurally-related EP(3) receptor-specific agonist ONO-AP-324, indicated that the inhibitory effect of non-prostanoids was specific for those compounds known to activate IP receptors. 7. The non-prostanoid prostacyclin mimetics also inhibited phospholipase C activity when stimulated by constitutively-active mutant Galpha(q)RC, Galpha(14)RC and Galpha(16)QL transiently expressed in CHO cells. These drugs did not inhibit adenylyl cyclase activity when stimulated by the constitutively-active mutant Galpha(s)QL. 8. These results suggest that non-prostanoid prostacyclin mimetics can specifically inhibit [(3)H]-inositol phosphate production by targeting G(q/11) and/or phospholipase C in CHO cells, and that this effect is independent of IP receptors.


Asunto(s)
Inhibidores Enzimáticos/farmacología , Epoprostenol/análogos & derivados , Receptores de Prostaglandina/fisiología , Fosfolipasas de Tipo C/antagonistas & inhibidores , Acetatos/farmacología , Adenilil Ciclasas/efectos de los fármacos , Adenilil Ciclasas/metabolismo , Alprostadil/farmacología , Animales , Células CHO , Supervivencia Celular/efectos de los fármacos , Cricetinae , AMP Cíclico/metabolismo , Relación Dosis-Respuesta a Droga , Epoprostenol/farmacología , Iloprost/farmacología , Imidazoles/farmacología , Fosfatos de Inositol/metabolismo , Oxazoles/farmacología , Fenoxiacetatos/farmacología , Piridinas/farmacología , Receptores de Epoprostenol , Receptores de Prostaglandina/agonistas , Receptores de Prostaglandina/genética , Transfección , Tritio , Fosfolipasas de Tipo C/metabolismo
12.
Br J Pharmacol ; 133(1): 13-22, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11325789

RESUMEN

1. Primary cultures of adult rat dorsal root ganglia (DRG) were prepared to examine the properties of prostacyclin (IP) receptors and prostaglandin E(2) (EP) receptors in sensory neurones. 2. IP receptor agonists, cicaprost and iloprost, stimulated adenylyl cyclase activity with EC(50) values of 22 and 28 nM, respectively. Prostaglandin E(1) (PGE(1)) and prostaglandin E(2) (PGE(2)) were 7 fold less potent than cicaprost and iloprost, with PGE(2) displaying a lower maximal response. 3. Adenylyl cyclase activation by iloprost, PGE(1) and PGE(2), but not by forskolin, was highly dependent on DRG cell density. Although the potency of iloprost and PGE(2) for stimulating adenylyl cyclase was unchanged, their maximal responses were significantly increased at low cell density. 4. Both IP and EP(2/4) receptors could be down-regulated by agonist pretreatment, however the presence of cyclo-oxygenase (COX) inhibitors did not prevent this apparent down-regulation of IP and EP(2/4) receptors at high DRG cell densities. 5. Stimulation of adenylyl cyclase by the neuropeptide calcitonin gene-related peptide was also decreased at high DRG cell density, whereas the responses to beta-adrenoceptor agonists were increased at high DRG cell density. 6. Addition of nerve growth factor (NGF), or the addition of anti-neurotrophin antibodies during the 5-day culture of DRG cells, had no effect on IP receptor-mediated responses. 7. These results indicate that G(s)-coupled receptors involved in nociception are regulated in a variable manner in adult rat sensory neurones, and that this cell density-dependent regulation may be agonist-independent for IP and EP(2/4) receptors.


Asunto(s)
Dinoprostona/análogos & derivados , Epoprostenol/análogos & derivados , Ganglios Espinales/metabolismo , Receptores de Prostaglandina/metabolismo , Adenilil Ciclasas/metabolismo , Envejecimiento/fisiología , Alprostadil/farmacología , Animales , Antineoplásicos/farmacología , Recuento de Células , Células Cultivadas , Colforsina/farmacología , AMP Cíclico/metabolismo , Inhibidores de la Ciclooxigenasa/farmacología , Dinoprostona/farmacología , Regulación hacia Abajo/efectos de los fármacos , Activación Enzimática/efectos de los fármacos , Epoprostenol/farmacología , Ganglios Espinales/citología , Ganglios Espinales/efectos de los fármacos , Ganglios Espinales/enzimología , Iloprost/farmacología , Masculino , Neuronas Aferentes/efectos de los fármacos , Neuronas Aferentes/enzimología , Neuronas Aferentes/metabolismo , Ratas , Ratas Sprague-Dawley , Receptores de Epoprostenol , Receptores de Prostaglandina/agonistas
13.
Br J Pharmacol ; 102(4): 887-95, 1991 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-1677298

RESUMEN

1. This paper describes the pharmacology of the novel alpha 2-adrenoceptor antagonist fluparoxan (GR 50360) which is currently being studied clinically as a potential anti-depressant. Idazoxan and yohimbine were included in many studies for comparison. 2. In the rat isolated, field-stimulated vas deferens and the guinea-pig isolated, field-stimulated ileum preparations, fluparoxan was a reversible competitive antagonist of the inhibitory responses to the alpha 2-adrenoceptor agonist UK-14304 with pKB values of 7.87 and 7.89 respectively. In the rat isolated anococcygeus muscle, fluparoxan was a much weaker competitive antagonist of the contractile response to the alpha 1-adrenoceptor agonist phenylephrine with a pKB of 4.45 giving an alpha 2: alpha 1-adrenoceptor selectivity ratio of greater than 2500. 3. In the conscious mouse, fluparoxan (0.2-3.0 mg kg-1) was effective by the oral route and of similar potency to idazoxan in preventing clonidine-induced hypothermia and antinociception. In the rat, UK-14304-induced hypothermia (ED50 = 1.4 mg kg-1, p.o. or 0.5 mg kg-1, i.v.) and rotarod impairment (ED50 = 1.1 mg kg-1 p.o. or 1.3 mg kg-1, i.v.) were antagonized by fluparoxan. Fluparoxan, 0.67-6 mg kg-1, p.o., also prevented UK-14304-induced sedation and bradycardia in the dog. 4. In specificity studies fluparoxan had low or no affinity for a wide range of neurotransmitter receptor sites at concentrations up to at least 1 x 10(-5) M. It displayed weak affinity for 5-HT1A (pIC50 = 5.9) and 5-HT1B (pKi = 5.5) binding sites in rat brain. 5. We conclude that fluparoxan is a highly selective and potent alpha 2-adrenoceptor antagonist. The density of rat brain [3H]-dihydroalprenolol binding sites was reduced by 26% when fluparoxan was administered chronically for 6 days at a dose of 12 mg kg- 1 orally twice daily. The down-regulation of beta-adrenoceptors by fluparoxan is consistent with its antidepressant potential.


Asunto(s)
Antagonistas Adrenérgicos alfa/farmacología , Piperoxano/análogos & derivados , Pirroles/farmacología , Agonistas alfa-Adrenérgicos/farmacología , Analgésicos/antagonistas & inhibidores , Animales , Aorta/efectos de los fármacos , Temperatura Corporal/efectos de los fármacos , Tartrato de Brimonidina , Clonidina/antagonistas & inhibidores , Cobayas , Frecuencia Cardíaca/efectos de los fármacos , Íleon/efectos de los fármacos , Técnicas In Vitro , Masculino , Músculo Liso/efectos de los fármacos , Norepinefrina/metabolismo , Piperoxano/farmacología , Equilibrio Postural/efectos de los fármacos , Quinoxalinas/antagonistas & inhibidores , Conejos , Ratas , Ratas Endogámicas , Receptores Adrenérgicos alfa/efectos de los fármacos , Receptores Adrenérgicos alfa/metabolismo , Receptores Dopaminérgicos/metabolismo , Receptores Histamínicos/metabolismo , Receptores Muscarínicos/metabolismo , Receptores de Serotonina/metabolismo , Conducto Deferente/efectos de los fármacos
14.
Artículo en Inglés | MEDLINE | ID: mdl-8832764

RESUMEN

The effects of three non-prostanoid prostacyclin mimetics on rat peritoneal neutrophil activity have been investigated and compared with the effects of the prostacyclin analogues cicaprost and iloprost. Cicaprost, iloprost, BMY 22389 (octimibate), BMY 42393 and BMY 45778 inhibited N-formyl-methionyl-leucyl-phenylalanine (FMLP)-stimulated neutrophil aggregation with IC50 values of 2.1, 4.5, 286, 462 and 20 nM, respectively. Cicaprost and iloprost produced clear concentration-related increases in [3H]cyclic AMP accumulation; EC50 values were 20 and 44 nM, respectively. In contrast, the three BMY compounds showed low efficacy as activators of adenylyl cyclase. The inhibitory effect of prostacyclin mimetics does not appear to depend on effects on intracellular calcium concentration, or on KATP channels. Extensive studies using cyclic AMP mimetics and antagonists suggest that the anti-aggregatory activity of the non-prostanoid prostacyclin mimetics on rat neutrophils may involve highly localized increases in cyclic AMP.


Asunto(s)
Acetatos/farmacología , Imidazoles/farmacología , Neutrófilos/efectos de los fármacos , Neutrófilos/metabolismo , Oxazoles/farmacología , Fenoxiacetatos/farmacología , Animales , Calcio/metabolismo , Agregación Celular/efectos de los fármacos , AMP Cíclico/antagonistas & inhibidores , AMP Cíclico/metabolismo , Diseño de Fármacos , Epoprostenol/análogos & derivados , Epoprostenol/farmacología , Gliburida/farmacología , Iloprost/farmacología , Masculino , N-Formilmetionina Leucil-Fenilalanina/farmacología , Inhibidores de Fosfodiesterasa/farmacología , Prostaglandinas Sintéticas/farmacología , Ratas , Ratas Sprague-Dawley , Receptores de Prostaglandina/agonistas
15.
Artículo en Inglés | MEDLINE | ID: mdl-9482170

RESUMEN

The inhibitory activity of prostaglandin E2 (PGE2) on rat neutrophil aggregation has been studied using the EP4-receptor antagonist AH23848B. While AH23848B antagonized the ability of PGE2 to inhibit neutrophil aggregation stimulated by platelet-activating factor (PAF), AH23848B showed agonist activity when neutrophils were stimulated by N-formyl-methionyl-leucyl-phenylalanine (FMLP). In addition, AH23848B showed weak stimulation of adenylyl cyclase activity and inhibited PGE2-stimulated [3H]cyclic AMP production by rat neutrophils, therefore AH23848B appears to be a partial agonist at EP4-receptors. These results suggest that rat neutrophils possess both inhibitory EP2- and EP4-receptors, and that FMLP-stimulated neutrophil aggregation is more highly coupled to inhibition by EP4-receptor activation than is PAF-stimulated neutrophil aggregation.


Asunto(s)
Compuestos de Bifenilo/farmacología , Agregación Celular/efectos de los fármacos , N-Formilmetionina Leucil-Fenilalanina/farmacología , Neutrófilos/efectos de los fármacos , Receptores de Prostaglandina E/metabolismo , Animales , AMP Cíclico/metabolismo , AMP Cíclico/farmacología , Dinoprostona/farmacología , Epoprostenol/análogos & derivados , Epoprostenol/farmacología , Masculino , N-Formilmetionina Leucil-Fenilalanina/antagonistas & inhibidores , Inhibidores de Fosfodiesterasa/farmacología , Factor de Activación Plaquetaria/farmacología , Pirrolidinonas/farmacología , Ratas , Ratas Sprague-Dawley , Rolipram
16.
Prostaglandins Leukot Essent Fatty Acids ; 54(3): 199-205, 1996 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8860108

RESUMEN

The effect of prostaglandins on neutrophil activation has been studied using the human promyelocytic leukemic cell line HL-60, differentiated with dimethyl sulfoxide (DMSO). Prostaglandin E(2) (PGE(2)) directly stimulated HL-60 cell aggregation with an EC(50) value of 30 nM. Studies with prostanoid receptor-selective agonists suggest that the activation of HL-60 cells by PGE(2) was mediated via the EP(2) receptor. Human neutrophils did not aggregate in response to PGE(2), but PGE(2) inhibited the N-formyl-methionyl-leucyl-phenylalanine (FMLP)-stimulated increase in intracellular calcium ([Ca(2+)i]) in both neutrophils and HL-60 cells. In contrast with the aggregation response to FMLP the aggregation response of HL-60 cells to PGE(2) was independent of extracellular calcium and did not involve mobilization of intracellular calcium.


Asunto(s)
Dinoprostona/farmacología , Células HL-60/efectos de los fármacos , Neutrófilos/metabolismo , Alprostadil/farmacología , Calcio/metabolismo , Agregación Celular/efectos de los fármacos , Humanos , N-Formilmetionina Leucil-Fenilalanina/farmacología , Neutrófilos/efectos de los fármacos , Prostaglandinas/farmacología , Receptores de Prostaglandina E/agonistas , Receptores de Prostaglandina E/metabolismo
17.
Artículo en Inglés | MEDLINE | ID: mdl-15062844

RESUMEN

The ability of prostacyclin analogues to stimulate adenylyl cyclase (AC) and phospholipase C (PLC) in Chinese hamster ovary (CHO) cells expressing cloned human (hIP) or cloned mouse (mIP) prostacyclin receptors has been compared. For hIP, the order of potency (pEC(50)) for stimulating AC and PLC pathways was similar: AFP-07 (9.3, 8.4)>cicaprost (8.3, 6.9), iloprost (7.9, 6.8)>taprostene (7.4, 6.8)>carbacyclin (6.9, 6.6), PGE(1) (6.6, 5.1). Although the standard IP agonists cicaprost and iloprost behaved similarly in both hIP and mIP receptor-expressing cells, carbacyclin and PGE(1) showed significantly higher potency at the mIP receptor, suggesting that the agonist recognition sites on hIP and mIP receptors are not identical. A further distinction between hIP and mIP receptors was found with taprostene, which had greater efficacy at hIP receptors (AC 94%, PLC 14%) than at mIP receptors (AC 77%, PLC 0%) (cicaprost=100% in each assay).


Asunto(s)
Epoprostenol/análogos & derivados , Prostaglandinas Sintéticas/farmacología , Receptores de Prostaglandina/agonistas , Adenilil Ciclasas/metabolismo , Animales , Células COS , Clonación Molecular , Cricetinae , Activación Enzimática/efectos de los fármacos , Epoprostenol/farmacología , Expresión Génica , Humanos , Iloprost/farmacología , Ratones , Ratas , Receptores de Epoprostenol , Receptores de Prostaglandina/genética , Proteínas Recombinantes/agonistas , Proteínas Recombinantes/genética , Transducción de Señal/efectos de los fármacos , Especificidad de la Especie , Fosfolipasas de Tipo C/metabolismo
18.
Urology ; 25(4): 393-4, 1985 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-3984130

RESUMEN

Percutaneous nephrostomy is a safe and highly effective means of urinary diversion. We report a case of unusual complications: severe peritonitis and massive intraperitoneal dissemination of carcinoma.


Asunto(s)
Adenocarcinoma , Neoplasias Peritoneales , Punciones/efectos adversos , Derivación Urinaria/efectos adversos , Adenocarcinoma/complicaciones , Adenocarcinoma/patología , Adulto , Humanos , Masculino , Invasividad Neoplásica , Neoplasias Peritoneales/complicaciones , Neoplasias Peritoneales/patología , Peritonitis/etiología
19.
Urology ; 25(2): 176-8, 1985 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-3969758

RESUMEN

A case of complete ureteral triplication is reported and a brief review of the literature is presented.


Asunto(s)
Coristoma/diagnóstico por imagen , Neoplasias Renales/diagnóstico por imagen , Uréter/anomalías , Preescolar , Femenino , Humanos , Urografía
20.
Urology ; 19(5): 486-8, 1982 May.
Artículo en Inglés | MEDLINE | ID: mdl-7080321

RESUMEN

A review of 59 children with severe hydronephrosis managed by cutaneous ureterostomy reveals that the procedure is safe, quick, and effective in draining the kidney. Although chronic bacteriuria is common, pyelonephritis is rare. The major drawback of this technique for temporary urinary diversion in children is that the subsequent urinary reconstruction is formidable and more difficult than primary repair. The complications of urinary diversion using this technique are low, however, and it may remain the safest form of diversion available for long-term use in children with dilated ureters.


Asunto(s)
Hidronefrosis/cirugía , Uréter/cirugía , Derivación Urinaria , Adolescente , Bacteriuria/etiología , Niño , Preescolar , Femenino , Humanos , Hidronefrosis/etiología , Masculino , Punciones , Estudios Retrospectivos , Vejiga Urinaria Neurogénica/etiología , Derivación Urinaria/efectos adversos , Infecciones Urinarias/etiología
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