ABSTRACT
After heavy dosages of sensory irritants osmiophilic whorls (mitochondrial lamellated bodies) are found in the mitochondria of the Type II cells of the lung. To obtain evidence of their nature, the lead/osmium (Pb/Os) ratio in these and other bodies after bimetallic staining was studied by electron probe X-ray analysis during transmission electron microscopy. To allow for inter-specimen variation the Pb/Os ratio was divided by the Pb/Os ratio for chromatin in the same cell, to give a "relative ratio". The values of the latter ranged from 1.4 for granules in an eosinophil leucocyte to 0.60-0.77 for lamellated osmiophilic bodies of Type II cells, 0.4 for nerve myelin, and 0.05 for fat globules. The Pb/Os ratio for mitochondrial lamellated bodies did not differ significantly from that for lamellated osmiophilic bodies (which are depots of lung surfactant) in the same cell. This is compatible with the mitochondrial lamellated bodies consisting of excess surfactant produced in response to stress. the method is capable of extension.
Subject(s)
Lung/ultrastructure , Mitochondria/analysis , Pulmonary Surfactants , Submitochondrial Particles/analysis , Animals , Dibenzoxazepines/pharmacology , Electron Probe Microanalysis , Lead/analysis , Lung/drug effects , Osmium/analysis , Prednisolone/pharmacology , Rats , Staining and LabelingSubject(s)
Cicatrix/pathology , Adolescent , Adult , Connective Tissue/ultrastructure , Female , Humans , Male , Microscopy, Electron, Scanning , Skin/ultrastructure , Suture Techniques , Time FactorsABSTRACT
The development of the lung from the glandular through the canalicular to the alveolar stages in the horse fetus is described. Traces of surfactant and occasional lamellated osmiophilic bodies representing intracellular surfactant were found at 150 days of gestation, some 40 to 60 days before the transition to the canalicular stage. During this transition some of the cuboidal cells of the glandular rosettes are transformed into cells of Types I and II, but the surfactant is not fully developed until 300 days or, in some foals, until after delivery.
Subject(s)
Horses/embryology , Lung/embryology , Pulmonary Surfactants/biosynthesis , Animals , Fetus , Gestational Age , Lung/ultrastructureSubject(s)
Lung/drug effects , Nitriles/toxicity , o-Chlorobenzylidenemalonitrile/toxicity , Animals , Lung/ultrastructure , RatsABSTRACT
The aims in a current study of dermis and scar tissue using the scanning electron microscope are: (1) to maintain the orientation of the specimen, (2) to preserve the in vivo architecture, and (3) to expose a satisfactory surface. A technique which best fulfils these requirements involves glutaraldehyde fixation of a splinted specimen, freeze-fracturing using a modified pair of pliers, freeze-drying again after washing. Consistently satisfactory specimens have been obtained, which provide information about fibre architecture and cell distribution.
