EFFECTS OF FUROSEMIDE, EXERCISE, AND ATROPINE ON TRACHEAL MUCUS TRANSPORT RATE IN HORSES

Effects of furosemide, exercise, and atropine on tracheal mucus transp ort rate (TMTR) in horses were investigated. Atropine (0.02 mg/kg of b ody weight) administered IV or by aerosolization significantly (P < 0. 05) decreased TMTR at 60, but not at 30 minutes after its administrati on in standing horses. Furosemide (1.0 mg/kg, IV) did not have any sig nificant effect on TMTR when measured at 2 or 4 hours after its admini stration in standing horses. Exercise alone or furosemide (1.0 mg/kg, IV) administration followed 4 hours later by exercise did not alter TM TR, compared with values for standing control or exercised horses admi nistered saline solution. Atropine (0.02 mg/kg, IV) administered after exercise significantly (I) < 0.05) decreased TMTR, compared with valu es for no exercise standing controls, for exercise after administratio n of saline solution, and for furosemide and exercise.