Pulmonary Function in Normal Rats

摘要

Pulmonary function tests (pfts) often are used in both humans and small animal species as physiologic biomarkers of pulmonary disease caused by the inhalation of toxic atmospheres. Physiologic biomarkers, used in conjunction with histopathological and biochemical biomarkers, can be used to diagnose disease, characterize dose/response relationships, assess disease pathogenesis, and indicate the degree of debilitation following pulmonary insult. We have developed methods to perform a battery of pfts that will be used to assess acute and chronic pulmonary toxicity in small animals exposed to inhaled toxins. The pfts developed can be used to assess physiologic responses in real-time during exposure, post exposure progress of induced pulmonary lesions, or both. Included are measures of ventilation (frequency, tidal volume, and minute ventilation), breath waveform analysis (flow derived parameters), dynamic pulmonary mechanics (compliance and resistance), static pulmonary mechanics (lung pressure-volume relationships and quasistatic compliance), sub-divisions of lung volume, pulmonary dynamics (forced maneuvers), distribution of ventilation (single breath N(sub 2) washout), gas exchange (carbon monoxide - single breath diffusing capacity, microcapnometry), and measurement of metabolic activity (microcapnometry). Sixty one untreated Long Evans rats were used to develop the assays and to form a historical database for normal animals. Values for a variety of indices of pulmonary function measured using the methods developed in our laboratory were comparable to those reported by several other investigators.