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G Miserocchi

Publications and source records attributed to G Miserocchi.

At least 91 records · Page 5Linked to original sources
PubMed1973

Localization of pulmonary stretch receptors in the airways of the dog.

1. During respiratory efforts against a closed airway, the afferent activity of vagal fibres from pulmonary stretch receptors does not appreciably increase during the inspiratory phase because the lung is prevented from expanding.2. Occlusion at different levels of the airways allows the localization of pulmonary stretch receptors in the tracheo-bronchial tree.3. 144 fibres from pulmonary stretch receptors on the left side of the tracheo-bronchial tree have been studied in eleven dogs and their localization was as follows: 17.4% in the upper half of the intrathoracic trachea, 27.1% in the lower half of the intrathoracic trachea and the carina, 11.1% in the main bronchus, 13.9% in the upper lobe and 30.5% in the lower lobe.4. From the surface area of the tracheo-bronchial tree at different levels on the assumption of a total of 2000 stretch receptors on each side, their average concentration was as follows: 34.8% receptors/cm(2) in the upper half of the intrathoracic trachea, 54.2/cm(2) in the lower half of the intrathoracic trachea, 56.8/cm(2) in the main bronchus, 0.37/cm(2) in the intrapulmonary airways.5. Occlusion of the main bronchus caused an increase of the eupnoeic oesophageal pressure swing by about 75% whereas occlusion of the inferior lobar bronchus led to an increase of only 20%. Therefore the reflex effects induced on the respiratory activity by occluding the airways at various levels show the greatest importance of the hilar portions of the airways where the concentration of pulmonary stretch receptors has been found to be greater.

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PubMed1973

Functional localization of pulmonary stretch receptors in the airways of the cat.

During a respiratory effort against a closed airway the afferent activity of vagal fibres from pulmonary stretch receptors does not appreciably increase during the inspiratory phase because the lung is prevented from expanding. The possibility to perform occlusions at different levels of the airways allows the localization of pulmonary stretch receptors in the tracheo-bronchial tree. 100 fibres from pulmonary stretch receptors of the left and right sides of the tracheo-bronchial tree have been studied in 3 cats and their localization found as follows: 10% in the higher half of the intrathoracic trachea, 22% in the lower half of the intrathoracic trachea and the carina, 7% in the main bronchus and 61% in the intrapulmonary airways. Knowing the surface area of the tracheo-bronchial tree at different levels and assuming total of 1200 stretch receptors from each side their average concentration resulted as follows: 50.0 receptors/cm2 in the higher half of the intrathoracic trachea, 108.0/cm2 in the lower half of the intrathoracic trachea and the carina, 213.0/cm2 in the main bronchus and 1.3/cm2 in the intrapulmonary airways.

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PubMedDate not supplied

Respiratory mechanics after 180 days space mission (EUROMIR'95).

The present study reports data on respiratory function of lung and chest wall following the 180 days long European - Russian EuroMir '95 space mission. Data reported refer to two subjects studied before the mission, on day 9 and 175 in flight and on days 1, 10, 12, 27 and 120 after return. In-flight vital capacity (VC) and expiratory reserve volume (ERV) were similar to those in supine posture, namely approximately 5% and approximately 30% less than in sitting posture. On day 1 after return, VC was reduced by approximately 30% in both postures. This reflected a decrease in ERV (approximately 0.5 L) and in IC (inspiratory capacity, approximately 1.7 L) that could be attributed to a marked weakening of the respiratory muscles. Regain of normal preflight values barely occurred 120 days after return. Post-flight pressure-volume curves of the lung, chest wall and total respiratory system are equal to preflight ones. The pressure-volume curve of the lung in supine posture is displaced to the right relative to sitting posture and shows a lower compliance. As far as the lung in-flight condition resembles that occurring in supine posture, this implies a lower compliance, a greater amount of blood in the pulmonary microvascular bed, a more homogeneous lung perfusion and therefore a greater microvascular filtration rate towards lung interstitium.

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