Cold weather exercise and airway cytokine expression.

Athletes who perform repeated exercise while breathing cold air have a high prevalence of asthmalike chronic airway disease, but the mechanism linking such activity to airway inflammation is unknown. We used a novel animal model (exercising horses) to test the hypothesis that exercise-induced chronic airway disease is caused by exposure of intrapulmonary airways to unconditioned air, resulting in the upregulation of cytokine expression. Bronchoalveolar lavage fluid (BALF) was obtained from eight horses 5 h after submaximal exercise while they breathed room temperature or subfreezing air in a random crossover design.

Regulation of the synthesis of choline-O-acetyltransferase and thymidylate synthetase in mouse neuroblastoma in cell culture.

The specific activity of mouse neuroblastoma choline-O-acetyltransferase (EC 2.3.1.