RT Journal Article SR Electronic T1 Morphofunctional changes in rats' lungs under exhausting physical training JF European Respiratory Journal JO Eur Respir J FD European Respiratory Society SP P2143 VO 44 IS Suppl 58 A1 Svetlana Sagidova A1 Mikhail Balykin A1 Alexandr Zharkov A1 Ruslan Nurmangaziev YR 2014 UL http://erj.ersjournals.com/content/44/Suppl_58/P2143.abstract AB The trial was conducted on male Wistar rats, 180-210 gramms (n=30). Rats performed swimming resistance training (10% of body weight, water temperature 28-31 C) daily, six times a week, during 30 days. In control groups on the 1, 5, 15 and 30 days of swimming trainings blood was taken from rats' caudal artery. Blood gas was measured with microaerotonometer AME (Radelkis, Denmark). Special histologic specimens were prepared; they were stained by hematoxylin-eosin (Van Gieson and Weigert staining protocol). Morphometry of respiratory tract and vessels on different levels of pulmonary artery branching was conducted with the help of a microscope.It is estimated that swimming during first five days is accompanied by size and alveoli cross sectional area, presence of protein exudate, diapedetic hemorrhage in alveoli opening and edema of alveoli walls. Segment, sub-segment and interlobular and intralobular arteries are vasodilated, their walls are loosened and edemic. Signs of hypoxemia (decrease of pO2, So2) and hypercapnia (pCO2 is increased from 37.2 p≤0.3 to 44.6 p≤0.4) are observed in arterial blood on the background of respiratory and metabolic acidosis (pH decreases from 7.41 p≤0,001 to 7.33 p≤0.002).On the 15th day reactive changes partially remain, and on the 30th day signs of morphofunctional adaptation are formed. They include increase in alveoli size and cross sectional area, pulmonary artery opening, and hypertrophy of vessel walls. At that period under physical loads increase of arterial pO2 and decrease of pCO2 is observed. It takes place on the background of compensated respiratory alkalosis which shows the increase of ventilation efficacy.