Total amount: € 0,00
Indexed/Abstracted in: BIOSIS Previews, EMBASE, Scopus, Emerging Sources Citation Index
Rubini A. 1, Carniel E. L. 2, Parmagnani A. 1, Bosco G. 1
1 Section of Physiology, Department of Biomedical Sciences, University of Padua, Padua, Italy;
2 Center of Mechanics of Biological Materials, University of Padua, Padua, Italy
Aim: Since a very low inflation flow rate renders the resistive pressure component of the inflation pressure practically negligible, the quasi-static pressure-volume curve of the respiratory system may be obtained by continuously recording the tracheal pressure. We aimed to validate this method of measurement of the elastic characteristics of the respiratory system in the small rat’s respiratory system by comparing pressure-volume data with a validated mathematical approach previously proposed for larger mammals.
Methods: Pressure-volume data were interpolated by a fitting polynomial equation and a very good agreement was found between experimental data and the mathematical approach.
Results: a) Pressure-volume curves of the respiratory system in healthy rats exhibit a lower and a higher inflection points. The alveolar recruitment process at low volume lasted till a volume of about 0.5-0.7 mL/100 g was inflated (lower inflection point), and the volume at which the elastic properties of the system became increasingly dependent on the mechanical characteristics of collagen fibers of the alveolar wall, rather than of elastin ones, resulted about 1.6-1.8 ml/100 in the rats (higher inflection point). b) A simple method to quantify inspiratory and total lung capacity in experimental animals is proposed. These were estimated respectively to be about 12 and 15-18 ml for the rat.
Conclusion: The low inflation flow rate method is confirmed to give reliable results in the small rat’s respiratory system too. A simple method to measure inspiratory and total lung capacity in experimental animals is proposed.