title: Ozone-induced inhibition of theophylline elimination in rabbits: effect of age and sex.
abstract: The effect of age and sex on the elimination of theophylline in New Zealand White rabbits was investigated following exposure to 0.3 ppm of ozone (O3) for 3.75 hr/day over 5 consecutive days. Animals were given air alone 5 to 7 days before and after the 5 days of O3 exposure. The elimination half-life of theophylline was significantly (p = 0.004) prolonged on Days 1 and 5 of O3 exposure in the rabbits greater than 2 years old, with no effect being seen in those 3 to 4 months old. No O3-induced change was seen in the apparent volume of distribution to account for the observed change in theophylline elimination half-life. The female rabbit in particular demonstrated this age-related effect; while in the male, variability prevented the observed difference from reaching significance. The results indicated inhibition of theophylline elimination by O3 in the rabbit depends on age and sex.
mesh_terms: D000375:Aging; D000818:Animals; D005260:Female; D006207:Half-Life; D008297:Male; D010126:Ozone / Q000633:toxicity*; D011817:Rabbits; D012737:Sex Factors; D013806:Theophylline / Q000378:metabolism*
chemical_list: D010126:Ozone; D013806:Theophylline