RESUMEN
LPS has an inhibitory effect on contractile activity of bovine mesenteric lymphatic vessels and nodes and causes a pronounced decrease in the tone and phase contractions. The selective inhibitor of inducible NO synthase, 1400W, and cyclooxygenase-2 selective inhibitor, dynastat, significantly attenuated the inhibitory effect of LPS. Dexamethasone interferes with the inhibitory effect of LPS on bovine lymphatic vessels and nodes. It was concluded that LPS stimulates expression of inducible NO synthase and cyclooxygenase-2 in endothelial and smooth muscle cells of lymphatic vessels and nodes. Dexamethasone has a pronounced protective effect on the contractile function of lymphatic vessels and nodes affected by LPS and suppresses the expression of inducible NO synthase and cyclooxygenase-2.
Asunto(s)
Antiinflamatorios/farmacología , Dexametasona/farmacología , Lipopolisacáridos/antagonistas & inhibidores , Ganglios Linfáticos/efectos de los fármacos , Vasos Linfáticos/efectos de los fármacos , Amidinas/farmacología , Animales , Bencilaminas/farmacología , Bovinos , Ciclooxigenasa 2/genética , Ciclooxigenasa 2/metabolismo , Células Endoteliales/citología , Células Endoteliales/efectos de los fármacos , Células Endoteliales/enzimología , Expresión Génica , Isoxazoles/farmacología , Lipopolisacáridos/farmacología , Ganglios Linfáticos/citología , Ganglios Linfáticos/enzimología , Vasos Linfáticos/citología , Vasos Linfáticos/enzimología , Masculino , Contracción Muscular/efectos de los fármacos , Músculo Liso/citología , Músculo Liso/efectos de los fármacos , Músculo Liso/enzimología , Miocitos del Músculo Liso/citología , Miocitos del Músculo Liso/efectos de los fármacos , Miocitos del Músculo Liso/enzimología , Óxido Nítrico Sintasa de Tipo II/genética , Óxido Nítrico Sintasa de Tipo II/metabolismo , Técnicas de Cultivo de TejidosRESUMEN
We studied the effect of IFNα-2b and IFNß-1a on phasic and tonic contractions of isolated bovine mesenteric lymphatic vessels and nodes. IFNα-2b and IFNß-1a in concentrations of 250-1000 U/ml produced dose-dependent negative chronotropic and inotropic effects on spontaneous phasic contractions and tonus of lymphatic vessels and nodes. In de-endothelialized lymphatic vessels and nodes, IFNα-2b and IFNß-1a in the same concentrations had less pronounced inhibitory effect on spontaneous contraction and tonus. L-NAME (100 µM) and charybdotoxin (0.1 µM with 0.5 µM apamine) significantly attenuated the inhibitory effect of IFNα-2b on phasic and tonic contractions of lymph nodes. L-NAME (100 µM) and indomethacin (10 µM) significantly reduced the IFNα-2b-induced inhibitory effect on phasic and tonic contractions of lymph node. These results indicate that IFNα-2b and IFNß-1a have a pronounced inhibitory effect on the phasic and tonic contractions of bovine mesenteric lymphatic vessels and nodes. The responses are endothelium-dependent and are determined by production of NO and endothelium-dependent hyperpolarizing factor by endotheliocytes in lymphatic vessels and by production of NO and prostacyclin by endotheliocytes in the lymphatic nodes.