Effects of sevoflurane anaesthesia on expression of vasoactive factors in rat lungs. Rats were anaesthetized with sevoflurane 4% for 0 h (CON), 2 h (2H), and 6 h (6H) (n=9 each group) before death. A2H were anaesthetized for 6 h, and then awoken for 2 h before death (n=9 each group). Expression ratios of ET-1 (a), NOS3 (b), and ADM (c) are plotted. Data are presented as box and whisker plots. The inter-quartile range is a measure of spread or dispersion. The box denotes the first quartile and the third quartile and is the difference between them. The range is a measure of dispersion and represents the difference between the lowest and highest scores in the data set. The whiskers are the two lines outside the box that extend to the highest and lowest data scores. The median is symbolized by a circle. *P<0.05 vs corresponding CON; ^†P<0.05 vs corresponding 2H; ^‡P<0.05 vs corresponding 6H.