RESUMEN
The beta-antagonistic activity of propranolol and metoprolol has been evaluated, in terms of inhibition of isoproterenol effects, "in vitro" (isolated right atria and tracheae) and "in vivo" in unanaesthetized normotensive and spontaneously hypertensive rats (SHR). Metoprolol resulted 13 - 6.4 - 14 times more cardioselective than propranolol in the three aforementioned experimental models, respectively. SHR, because of its decreased baroceptor sensitivity to trigger the tachycardic reflex, proves a good model for the evaluation of beta 1 antagonistic activity of "cardioselective" beta- blockers, which could be underevaluated in the normotensive rat. Moreover, the agonistic activity of isoproterenol has been compared in normo and hypertensive rats in order to ascertain whether the different number of beta 1 receptors in the two strains could influence the biological response to their stimulation and/or or blockade.
Asunto(s)
Hipertensión/fisiopatología , Metoprolol/farmacología , Propranolol/farmacología , Receptores Adrenérgicos beta/efectos de los fármacos , Animales , Presión Sanguínea/efectos de los fármacos , Frecuencia Cardíaca/efectos de los fármacos , Isoproterenol/farmacología , Masculino , Presorreceptores/efectos de los fármacos , Ratas , Ratas Endogámicas , Receptores Adrenérgicos beta/clasificaciónAsunto(s)
Antiinflamatorios/farmacología , Ácidos Indolacéticos/farmacología , Prostaglandinas/biosíntesis , Animales , Ácidos Araquidónicos/metabolismo , Diarrea/tratamiento farmacológico , Femenino , Mucosa Gástrica/metabolismo , Técnicas In Vitro , Indometacina/farmacología , Trabajo de Parto/efectos de los fármacos , Pulmón/metabolismo , Masculino , Músculo Liso/efectos de los fármacos , Embarazo , Ratas , Contracción Uterina/efectos de los fármacosAsunto(s)
Carisoprodol/farmacología , Vaciamiento Gástrico/efectos de los fármacos , Animales , Antipirina/análogos & derivados , Antipirina/farmacología , Química Encefálica/efectos de los fármacos , Carisoprodol/sangre , Carisoprodol/metabolismo , Masculino , Ratones , Fenolsulfonftaleína/farmacología , Equilibrio Postural/efectos de los fármacos , Ratas , Especificidad de la Especie , Factores de TiempoRESUMEN
The bronchodilator activity of four analogues of PGE2: 13,14-didehydro-PGE2 (I), 20-methyl-13,14-didehydro-PGE2 (II), 16 S-methyl-13,14-didehydro-PGE2 (III) and 16 R-methyl-13,14-didehydro-PGE2 (IV) was studied in vivo and in vitro. The potency of III and IV when administered by aerosol to conscious guinea pigs was four times that of PGE2 in protecting against histamine-induced convulsion; I and II were less active. Compound III administered by aerosol to anaesthetized guinea pigs was six times more potent than PGE2 in protecting against i.v. histamine-induced increase of intractracheal pressure and the effect was longer-lasting. All the compounds caused relaxation of carbachol-induced tone in isolated guinea pig tracheal strips.
Asunto(s)
Broncodilatadores , Dinoprostona/análogos & derivados , Anestesia , Animales , Bronquios/efectos de los fármacos , Cobayas , Histamina/farmacología , Técnicas In Vitro , Masculino , Contracción Muscular/efectos de los fármacos , Músculo Liso/efectos de los fármacos , Prostaglandinas E Sintéticas/farmacología , Relación Estructura-Actividad , Factores de Tiempo , Tráquea/efectos de los fármacosAsunto(s)
Prostaglandinas E Sintéticas/farmacología , Animales , Diarrea/inducido químicamente , Jugo Gástrico/metabolismo , Cobayas , Humanos , Técnicas In Vitro , Masculino , Contracción Muscular/efectos de los fármacos , Músculo Liso/efectos de los fármacos , Prostaglandinas E Sintéticas/uso terapéutico , Ratas , Ratas Endogámicas , Úlcera Gástrica/tratamiento farmacológico , Úlcera Gástrica/etiología , Estrés Psicológico , Relación Estructura-ActividadAsunto(s)
Jugo Gástrico/metabolismo , Mucosa Gástrica/efectos de los fármacos , Prostaglandinas Sintéticas/farmacología , Animales , Compuestos de Betanecol/antagonistas & inhibidores , Bombesina/antagonistas & inhibidores , Gatos , Desoxiglucosa/antagonistas & inhibidores , Perros , Antagonistas de los Receptores Histamínicos , Antagonistas de Insulina , Pentagastrina/antagonistas & inhibidores , Prostaglandinas E/farmacología , Ratas , Especificidad de la EspecieAsunto(s)
Prostaglandinas/síntesis química , Abortivos , Animales , Colon/efectos de los fármacos , Femenino , Cobayas , Hidroxiprostaglandina Deshidrogenasas/metabolismo , Técnicas In Vitro , Contracción Muscular/efectos de los fármacos , Prostaglandinas/metabolismo , Prostaglandinas/farmacología , Ratas , Relación Estructura-Actividad , Útero/efectos de los fármacosRESUMEN
The biological activities of 8,12-diiso-PGE2 (ent-11,15-epi-PGE2), PGE2 and PGF2alpha have been compared in a series of pharmacological preparations intended to differentiate between F and E type of activity. Similar to PGF2alpha but unlike PGE2, 8,12-diiso-PGE2 increased the tone of isolated smooth muscle preparations of guinea pig trachea, guinea pig colonic circular layer, rabbit Fallopian tubes. The stimulation effect of 8,12-diiso-PGE2 and PGF2alpha on visceral smooth muscle was also shown in vivo: the two drugs were in all instances able to increase the miogenic activity and tone of rabbit uterus in situ, while these were depressed by PGE2. 8,12-diiso-PGE2 decreased pulmonary compliance and increased pulmonary vascular resistance in the anaesthetized cat; PGE2 always decreased pulmonary vascular resistance, while leaving pulmonary compliance unaltered. The possibility is suggested that 8,12-diiso-PGE2 acts on PGF receptor in different tissues.