Comparative pharmacokinetics and bioavailability of oxolinic acid and oxytetracycline in rainbow trout (Oncorhynchus mykiss)

Abstract

1. The pharmacokinetics and bioavailability of oxolinic acid and oxytetracycline were studied in rainbow trout at a water temperature of 16 degrees C after intravascular (10 and 20 mg/kg, respectively) and oral (75 mg/kg) dosing. 2. The pharmacokinetics were best described by a two-compartment open model giving distribution half-lives of 0.31 h and 1.53 h, and elimination half-lives of 69.7 h and 60.3 h for oxolinic acid and oxytetracycline, respectively. The respective volumes of distribution (Vdarea) were 1.94 l/kg and 1.34 l/kg. 3. The apparent oral bioavailability for oxolinic acid and oxytetracycline was 13.6% and 5.6%. 4. The plasma protein binding was 27% for oxolinic acid and 55% for oxytetracycline. 5. Both drugs were well tolerated, the acute oral toxicities (LD50) exceeding 4000 mg/kg.

Protective effect of propolis against oxidative stress and immunosuppression induced by oxytetracycline in rainbow trout (Oncorhynchus mykiss, W.)

“…The drugs that are concentrated or retained in immune tissues could interact with immune cells and thus influence the immune responses. OTC is known to have good tissue penetration [1] and to accumulate and be retained in scales, bone tissue, liver, muscle, plasma and the pronephros, an important lymphoid organ of fish [8,11,84,85]. We speculate that the cause of the immunosuppression may be intoxication as a consequence of OTC accumulation in immune system organs, such as the kidney, spleen, liver and heart.…”

“…OTC is used in the treatment of systemic bacterial infections because it is active against a wide range of gram-negative and gram-positive organisms, has economic advantages, and is legally available [1]. OTC is primarily bacteriostatic and exerts its antimicrobial effect by inhibiting protein synthesis [2].…”

Residual pharmaceutically active compounds (PhACs) in aquatic environment - status, toxicity and kinetics: a review

“…Furthermore, in crustaceans the volume of haemolymph comprises 22% of the total body weight, compared to 5% in finfish (Barron et al, 1988;Plakas et al, 1990), with the volume of distribution directly related to tissue binding and inversely related to plasma protein binding. Protein binding in finfish is always higher than that found in crustaceans, e.g., 23 and 14-21% in P. japonicus (Uno, 2004) and P. setiferus (Reed et al, 2004), respectively, compared to 51-55% in O. mykiss (Bjorklund and Bylund, 1991;Uno et al, 1997) and 68% in P. altivelis (Uno, 1996). A diminished binding of plasma protein results in an increase in extravascular distribution.…”

Pharmacokinetics of Nalidixic Acid and Sodium Nifurstyrenate in Cultured Fish Following Bolus Intravascular Administration.

“…In rainbow trout the protein bindings of NA was low. The protein bind ings of oxolinic acid and oxytetracycline were 27% and 55% in rainbow trout (Bjorklund and Bylund, 1991), respectively. Stehly and Plakas (1993) re ported protein binding of nitrofurantoin in channel catfish were from 62% to 50%.…”

“…In our study, pharmacoki netic analysis for the serum levels of drugs was performed using one-, two-or three-compartment open models using the nonlinear least squares pro gram MULTI (Yamaoka et al, 1981) and 720 ml/kg/h for nitrofurantoin in channel catfish by Bjorklund and Bylund (1991) and Stehly and Plakas (1993) . The protein binding of drug can influence the concentration of active drug in the blood and its distribution in the tissues.…”