title: Probenecid infusion in mares: effect on para-aminohippuric acid clearance.
abstract: Para-aminohippuric acid (PAHA, 0.1 mg/min/kg of body weight) was infused IV into 2 mares, followed by concurrent IV infusion of PAHA and probenecid (0.075, 0.15, 0.25, or 0.35 mg of probenecid/min/kg). Probenecid infusion reduced the clearance of PAHA at serum probenecid concentrations greater than 55 micrograms/ml. At 12-hour intervals, probenecid (in 5 repeated doses - 50, 75, 100, or 200 mg/kg) was administered by gavage to 2 mares. Mean serum probenecid concentration was greater than 55 micrograms/ml for all dosages. At dosages less than 200 mg/kg, accumulation of probenecid in the serum was minimal from the 1st to the 5th dose. At a dosage of 200 mg/kg, probenecid accumulated in the serum from the 1st to the 5th dose. Intragastric administration of 5 doses of probenecid (75 mg/kg) at 12-hour intervals to 6 mares reduced the clearance of PAHA by 50%. Bioavailability of probenecid was 117 and 102% for 2 mares after a single intragastric dose, compared with a single IV dose.
authors.affiliation: Department of Medical Sciences, College of Veterinary Medicine, University of Florida, Gainesville 32610.
authors.forename: R
authors.initials: R
authors.lastname: Gronwall
authors.forename: M P
authors.initials: MP
authors.lastname: Brown
mesh_terms: D000284:Administration, Oral; D000618:Aminohippuric Acids / Q000493:pharmacokinetics*; D000818:Animals; D001682:Biological Availability; D005260:Female; D006736:Horses / Q000378:metabolism*; D007262:Infusions, Intravenous; D008433:Mathematics; D011339:Probenecid / Q000008:administration & dosage / Q000493:pharmacokinetics / Q000494:pharmacology*; D012984:Software; D010130:p-Aminohippuric Acid / Q000008:administration & dosage / Q000493:pharmacokinetics*
chemical_list: D000618:Aminohippuric Acids; D011339:Probenecid; D010130:p-Aminohippuric Acid