RESUMEN
Cloricromene is a coumarin derivative without anticoagulant activities that has recently been found to decrease myocardial infarct size after an ischemic-reperfusion injury. This study seeks to determine when the cardioprotective action of cloricromene is exerted in an in vivo rabbit model of ischemic-reperfusion injury. Forty-nine rabbits subjected to 30 min of coronary occlusion and 120 min of reperfusion were randomized into five groups: VEH (n = 11) received saline vehicle; IR (n = 9) received an infusion of cloricromene starting at the onset of ischemia at 8 micrograms.kg-1.min-1; R(-5)(n = 9) and R(+30)(n = 9) received an infusion of cloricromene at 8 micrograms.kg-1.min-1 starting 5 min before reperfusion and 30 min after reperfusion, respectively; and RB(-5)(n = 11) received 300 micrograms/kg bolus of cloricromene 5 min before reperfusion followed by an infusion of 8 micrograms.kg-1.min-1. All infusions were continued until the end of the reperfusion period. Myocardial infarct size was significantly reduced in groups IR, R(-5), and RB(-5). We conclude that cloricromene's effective time of action occurs prior to the first 30 min of the reperfusion period.
Asunto(s)
Anticoagulantes/administración & dosificación , Cromonar/análogos & derivados , Cumarinas/administración & dosificación , Infarto del Miocardio/patología , Daño por Reperfusión Miocárdica/patología , Reperfusión Miocárdica , Animales , Presión Sanguínea , Cromonar/administración & dosificación , Frecuencia Cardíaca , Masculino , Infarto del Miocardio/tratamiento farmacológico , Infarto del Miocardio/fisiopatología , Daño por Reperfusión Miocárdica/tratamiento farmacológico , Daño por Reperfusión Miocárdica/fisiopatología , Miocardio/patología , Conejos , Factores de TiempoAsunto(s)
Anticuerpos Antivirales/sangre , Enfermedades de los Bovinos/microbiología , Infecciones por Coronaviridae/veterinaria , Disentería/veterinaria , Torovirus/inmunología , Virosis/veterinaria , Animales , Bovinos , Enfermedades de los Bovinos/inmunología , Infecciones por Coronaviridae/epidemiología , Infecciones por Coronaviridae/inmunología , Disentería/inmunología , New England/epidemiología , Estudios Seroepidemiológicos , Virosis/epidemiología , Virosis/inmunologíaRESUMEN
Acute and convalescent sera were collected from 8 dairy herds with classic clinical features of winter dysentery. An enzyme-linked immunosorbent assay was used to measure coronavirus antibody titers, employing calf diarrhea coronavirus as antigen. Twenty-two of the 35 animals tested (63%) showed a greater than or equal to 4-fold seroconversion. Adult cattle in all 8 herds seroconverted. These findings complement previously reported immunoperoxidase and electron microscopic evidence, suggesting an etiologic role for an enteric coronavirus in this disease.
