RESUMEN
Nedocromil sodium is a nonsteroidal anti-inflammatory drug used to control asthmatic attacks. Our hypothesis is that nedocromil sodium inhibits virus-induced airway inflammation, a common trigger of asthma. We nebulized nedocromil sodium into beagle dogs (n = 10, mean +/- SEM ages: 149 +/- 13 days) before and after inoculation with canine adenovirus type 2 (CAV2). Control dogs (n = 10) received saline aerosols and were either infected with CAV2 (Sal/CAV2, n = 7, mean +/- SEM ages: 140 +/- 11 days) or were not infected (Sal/Sal, n = 3, ages: 143 +/- 0 days). All dogs were anesthetized with choralose (80 mg/kg i.v.), intubated, and mechanically ventilated. Pulmonary function tests and bronchoalveolar lavage (BAL) were performed using standard techniques. Pulmonary function tests revealed no significant change between the nedocromil sodium and non-nedocromil-treated groups. The percentage of infected bronchioles was quantitated as the number of inflamed airways of 40 bronchioles examined times 100 for each dog. Nedocromil-treated dogs had significantly (p < 0.05) less mucosal inflammation (mean +/- SEM, 39% +/- 5%), epithelial denudation (36% +/- 5%), and BAL neutrophilia (11 +/- 3) than did Sal/CAV2 dogs (51% +/- 6%, 57% +/- 4%, and 33% +/- 8%, respectively). We concluded that pretreatment with nedocromil sodium aerosols attenuated CAV2-induced airway inflammation in these beagle puppies.
Asunto(s)
Infecciones por Adenoviridae/prevención & control , Adenovirus Caninos , Antiasmáticos/uso terapéutico , Bronquiolitis Viral/prevención & control , Nedocromil/uso terapéutico , Infecciones por Adenoviridae/patología , Adenovirus Caninos/fisiología , Animales , Bronquiolitis Viral/patología , Líquido del Lavado Bronquioalveolar/citología , Recuento de Células , Modelos Animales de Enfermedad , Perros , Pulmón/efectos de los fármacos , Pulmón/fisiología , Neutrófilos/efectos de los fármacos , Pruebas de Función Respiratoria , Mucosa Respiratoria/efectos de los fármacos , Mucosa Respiratoria/patologíaRESUMEN
Cardiopulmonary bypass has been implicated in triggering a multisystem inflammatory response caused by blood contact with the artificial surfaces of the circuit. This leads to increased morbidity levels because of cytotoxic enzymes released from activated neutrophils. Recently, it was discovered that certain inflammatory mediators are permeable to the membrane of the hemoconcentrator. As a result, this study was undertaken to quantitatively characterize the nature of this movement by deriving a sieving coefficient (S) for four inflammatory mediators: myeloperoxidase, elastase, interleukin-6, and lactoferrin. The results show no permeability through the hemoconcentrator for the two neutrophil derived enzymes myeloperoxidase and elastase (S = 0, p > 0.05). Conversely, although larger than the pore size of the hemoconcentrator, lactoferrin sieves through unrestricted (S = 1.030 +/- 0.037, p < 0.0001). Interleukin-6 is removed in concentrations greater than those found in the blood, which yields a sieving coefficient significantly greater than 1.0 (S = 1.246 +/- 0.042, p < 0.0001). In addition to sieving coefficients, this study offers theories as to why these mediators acted as such. One conclusion is that certain mediators are efficaciously removed by the hemoconcentrator and, with additional study, may result in an attenuated inflammatory response.
Asunto(s)
Puente Cardiopulmonar/efectos adversos , Hemofiltración/métodos , Mediadores de Inflamación/sangre , Mediadores de Inflamación/aislamiento & purificación , Anciano , Humanos , Inflamación/etiología , Inflamación/prevención & control , Mediadores de Inflamación/química , Interleucina-6/sangre , Interleucina-6/aislamiento & purificación , Lactoferrina/sangre , Lactoferrina/aislamiento & purificación , Elastasa de Leucocito/sangre , Elastasa de Leucocito/aislamiento & purificación , Masculino , Persona de Mediana Edad , Peso Molecular , Neutrófilos/enzimología , Peroxidasa/sangre , Peroxidasa/aislamiento & purificaciónRESUMEN
BACKGROUND: Advances in myocardial preservation techniques and immunosuppressive drug therapy have resulted in heart transplantation as an acceptable treatment for end-stage heart failure. However, excessive periods of global myocardial ischemia followed by reperfusion can progress to irreversible graft injury. It has been reported that cyclosporine A (in addition to its well-characterized immunosuppressive actions) can blunt certain features of ischemia and reperfusion injury. This study was performed to examine the ability of cyclosporine A to attenuate such injury in a model of heart transplantation. METHODS: Twenty rabbit heterotopic transplants were divided into four study groups: (1) 30-minute ischemic control hearts; (2) 30-minute ischemic cyclosporine A-treated hearts; (3) 4-hour ischemic control hearts; and (4) 4-hour ischemic cyclosporine A-treated hearts. A single dose of cyclosporine A (10 mg/kg intravenously) or vehicle was administered to both the donor and recipient rabbits 45 minutes before heart explantation and heart transplantation, respectively. RESULTS: After transplantation and 30 minutes of reperfusion, the 4-hour ischemic control hearts showed a significant (p < 0.01) leftward shift in the left ventricular end-diastolic pressure versus left ventricular volume curve compared with the 30-minute ischemic control hearts. This finding represents higher end-diastolic pressures and incomplete diastolic relaxation caused by ischemia and reperfusion. Cyclosporine A administration to the donor and recipient rabbits resulted in a significant improvement (p < 0.01) in diastolic relaxation (shift in the left ventricular end-diastolic pressure versus left ventricular volume curve back to the right) compared with 4-hour ischemic control hearts. Cyclosporine A-treated hearts also showed significant improvements in the rate of diastolic pressure fall (p < 0.05) and tau (the isovolumetric pressure decay constant) (p < 0.01) compared with ischemic control hearts. CONCLUSIONS: These results indicate that single doses of cyclosporine A to both the donor and recipient inhibit the dysfunction in extent and rate of left ventricular relaxation caused by prolonged global ischemia and reperfusion. Possible mechanisms for cyclosporine A's myocardial protective actions are presented in the discussion.