الملخص
The morphology of the rat lung was studied by light microscopy in different situations: after surgical and pharmacological castration and after administration of testosterone to the castrated rat to determine if the androgen is required to maintain the normal morphology of the lung. We also determined the effect of flutamide on the phospholipid composition of both the surfactant and microsomes of the lung. Rats were separated into five groups: I - control non-castrated rats, II - castrated rats sacrificed 21 days after castration, III - castrated rats that received testosterone daily from day 2 to day 21 after castration, IV - castrated rats that received testosterone from day 15 to day 21 after castration, and V - control rats injected with flutamide for 7 days. The amount of different phospholipids in the surfactant and microsomes of the lung was measured in group I and V rats. At the light microscopy level, the surgical and pharmacological castration provoked alterations in the morphology of the lung, similar to that observed in human lung emphysema. The compositions of surfactant and microsomes of the lung were similar to those previously reported by us for the surgically castrated rats. These results indicate that androgens are necessary for the normal morphology as well as for some metabolic aspects of the lung.
الموضوعات
Animals , Male , Rats , Androgen Antagonists/pharmacology , Flutamide/pharmacology , Gonadal Steroid Hormones/pharmacology , Lung/cytology , Microsomes/drug effects , Orchiectomy , Pulmonary Surfactants/drug effects , Testosterone/pharmacology , Lung/metabolism , Microsomes/chemistry , Orchiectomy/adverse effects , Phospholipids/analysis , Pulmonary Surfactants/chemistry , Rats, Wistarالملخص
Since the most characeristic feature of paraquat poisoning is lung damage, a prospective controlled study was performed on excised rat lungs in order to estimate the intensity of lesion after different doses. Twenty-five male, 2-3-month-old non-SPF Wistar rats, divided into 5 groups, received paraquat dichloride in a single intraperitoneal injection (0,1, 5,, 25, or 50 mg/kg body weight) 24 h before the experiment. Static pressure-volume (PV) curves were performed in air-and saline-filled lungs; an estimator of surface tension and tissue works was computed by integrating the area of both curves and reported as work/ml of volume displacement. Paraquat induced a dose-dependent increase of inspiratory surface tension work that reached a significant two-fold order of magnitude for 25 and 50 mg/kg body weight (P<0.05, ANOVA), sparing lung tissue. This kind of lesion was probably due to functional abnormalities of the surfactant system, as was shown by the increase in the hysteresis of the paraquat group at the highest doses. Hence, paraquat poisoning provides a suitable model of acute lung injury with alveolar instability that can be easily used in experimental protocols of mechanical ventilation.
الموضوعات
Animals , Male , Rats , Herbicides/toxicity , Lung/drug effects , Lung/injuries , Paraquat/toxicity , Pulmonary Surfactants/drug effects , Acute Disease , Disease Models, Animal , Dose-Response Relationship, Drug , Inspiratory Capacity , Prospective Studies , Rats, Wistar , Respiration, Artificialالملخص
In order to observe the effects of serum albumin and fibrinogen on biophysical surface properties and the morphology of pulmonary surfactant in vitro, we measured the surface adsorption rate, dynamic minimum and maximum surface tension (min-, max-ST) by Pulsating Bubble Surfactometer, and demonstrated ultrastructures on a series of mixtures with varying concentrations of albumin or fibrinogen and Surfactant-TA. The albumin and fibrinogen significantly inhibited the adsorption rate and ST-lowering properties of surfactant through increasing STs of adsorption rate, min-ST, and max-ST. The characteristic morphology of the Surfactant-TA changed from lamellar rod-like structure with open ends into spherical structures with loss of their open ends by mixing with albumin or fibrinogen. These inhibitory effects of albumin and fibrinogen on surface properties of surfactant were dependent upon the increasing concentration of albumin or fibrinogen. We concluded that albumin and fibrinogen significantly altered surfactant function and its ultrastructural morphology in vitro. These findings support the concept that albumin and fibrinogen-induced surfactant dysfunction may play an important role in the pathophysiology of adult respiratory distress syndrome, and this adverse effect of albumin and fibrinogen on surfactant might be overcome by administration of large doses of exogenous surfactant.
الموضوعات
Cattle , Humans , Adsorption , Animals , Fibrinogen/pharmacology , Pulmonary Surfactants/ultrastructure , Pulmonary Surfactants/drug effects , Serum Albumin, Bovine/pharmacology , Surface Propertiesالموضوعات
Humans , Infant, Newborn , Patient Care Management/standards , Hyaline Membrane Disease/complications , Risk Factors , Hyaline Membrane Disease/diagnosis , Hyaline Membrane Disease/drug therapy , Medical Errors , Practice Guidelines as Topic , Pulmonary Surfactants/drug effects , Pulmonary Surfactants/therapeutic useالموضوعات
Humans , Animals , Infant, Newborn , Infant , Child, Preschool , Child , Adolescent , Adult , Middle Aged , Fluorocarbons/therapeutic use , Respiration, Artificial/methods , Respiratory Distress Syndrome, Newborn/therapy , Fluorocarbons , Hernia, Diaphragmatic/congenital , Hernia, Diaphragmatic/therapy , Pulmonary Gas Exchange/drug effects , Pulmonary Surfactants/drug effects , Respiratory Distress Syndrome, Newborn/physiopathology , Respiratory Distress Syndrome/physiopathology , Pulmonary Ventilationالموضوعات
Humans , Female , Pregnancy , Alkaline Phosphatase , Fetal Organ Maturity , Hyaline Membrane Disease , Amniotic Fluid/physiology , Obstetric Labor, Premature , Oligohydramnios/diagnosis , Polyhydramnios/diagnosis , Pulmonary Surfactants/drug effects , Respiratory Distress Syndrome, Newborn , Amniocentesis , Amniocentesis/adverse effects , Collagen , Creatinine , Fetal Membranes, Premature Rupture/therapy , Fibronectins , Phospholipids/analysis , Phospholipids , gamma-Glutamyltransferase , Hyaline Membrane Disease/physiopathology , Infant, Premature , Rh Isoimmunization/diagnosis , Amniotic Fluid/cytology , Meconium Aspiration Syndrome/therapy , Obstetric Labor, Premature/diagnosis , Oligohydramnios/complications , Oligohydramnios/etiology , Phosphatidylglycerols , Phosphatidylinositols , Polyhydramnios/etiology , Polyhydramnios/therapy , Pregnancy in Diabetics , Pregnancy Trimester, Third , Pulmonary Surfactants/biosynthesis , Pulmonary Surfactants/therapeutic use , Respiratory Distress Syndrome, Newborn/etiology , Respiratory Distress Syndrome, Newborn/physiopathologyالموضوعات
Rabbits , Humans , Pregnancy , Infant, Newborn , Animals , Female , Glucocorticoids/therapeutic use , Pulmonary Surfactants/drug effects , Respiratory Distress Syndrome, Newborn/drug therapy , Thyrotropin-Releasing Hormone/therapeutic use , Betamethasone/therapeutic use , Glucocorticoids/therapeutic use , Fetal Organ Maturity , Lung , Respiratory Distress Syndrome, Newborn/prevention & control , Thyrotropin-Releasing Hormone/administration & dosage , Thyrotropin-Releasing Hormone/pharmacologyالملخص
El ambroxol es un medicamento útil en el tratamiento del síndrome de dificultad respiratoria neonatal, dada su capacidad de elevar la producción y liberación de surfactante y de mejorar los mecanismos pulmonares. Por otro lado, previene la atelectasia pulmonar postextubación, adicionándose a las características anteriores su efecto mucolítico y mucocinético. En el presente trabajo se hace una revisión para ofrecer al lector una visión amplia del medicamento y sus posibles aplicaciones en pediatría. No se pretende sugerir que el ambroxol desplace las otras posibilidades terapéuticas, sino presentarlo como un medicamento que ofrece nuevas alternativas
الموضوعات
Infant, Newborn , Dogs , Mice , Rabbits , Rats , Humans , Animals , Respiratory Distress Syndrome, Newborn/drug therapy , Respiratory Distress Syndrome, Newborn/therapy , Pulmonary Surfactants/drug effects , Ambroxol/therapeutic use , Ambroxol/pharmacologyالموضوعات
Humans , Infant, Newborn , Hyaline Membrane Disease/complications , Patient Care Management/standards , Risk Factors , Hyaline Membrane Disease/diagnosis , Hyaline Membrane Disease/drug therapy , Medical Errors , Practice Guidelines as Topic , Pulmonary Surfactants/drug effects , Pulmonary Surfactants/therapeutic useالموضوعات
Female , Rabbits , Humans , Pregnancy , Infant, Newborn , Animals , Glucocorticoids/therapeutic use , Thyrotropin-Releasing Hormone/therapeutic use , Pulmonary Surfactants/drug effects , Respiratory Distress Syndrome, Newborn/drug therapy , Betamethasone/therapeutic use , Glucocorticoids/therapeutic use , Thyrotropin-Releasing Hormone/administration & dosage , Thyrotropin-Releasing Hormone/pharmacology , Fetal Organ Maturity/drug effects , Lung/drug effects , Respiratory Distress Syndrome, Newborn/prevention & controlالملخص
Pulmonary surfactant activity of healthy male albino rats was estimated in terms of the maximum and minimum surface tension values of alveolar washings and the phospholipid content of the extract. The results obtained in these (control) animals were compared with those in three groups of animals treated with therapeutic doses of terbutaline, adrenaline and aminophylline. A significant decrease in the surface tension values without a significant increase in the phospholipid content was observed with aminophylline, whereas a significant increase in phospholipid concentration without a significant decrease in surface tension values was observed in case of terbutaline and adrenaline. These findings suggest that aminophylline, in addition to a bronchodilator action, lowers the elastic resistance of lung. The study also indicates caution in interpreting phospholipid concentration as surfactant activity.