Kinetics and intrapulmonary disposition of tilmicosin after single and repeated oral bolus administrations to rabbits.
Tilmicosin (TIM, Pulmotil) was administered to eight rabbits by oral gavage at a dose of 12.5 mg/kg body weight for 2, 5, and 7 days, and its plasma kinetics and intrapulmonary disposition were investigated. TIM concentrations in plasma samples collected after days 1 and 6 of treatment were measured by high-performance liquid chromatography with ultraviolet detection. The pharmacokinetic parameters, obtained by non-compartmental analysis of TIM plasma concentrations, did not show any significant variations between days 1 and 6. From the second day of treatment, TIM concentrations attained in lung tissue and pulmonary alveolar macrophages (PAM) exceeded those in plasma by 7- and 400-fold, respectively, and high levels were maintained in lung tissues during the entire treatment duration. After the first day of withdrawal, a fast decline in TIM levels in both plasma and lung tissue was observed, but in PAM, much higher concentrations were maintained after 3 days of TIM withdrawal.
Gallina
G
G
Dipartimento di Sanità Pubblica, Patologia Comparata ed Igiene Veterinaria, Legnaro, PD, Italy.
Lucatello
L
L
Drigo
I
I
Cocchi
M
M
Scandurra
S
S
Agnoletti
F
F
Montesissa
C
C
D000284:Administration, Oral; D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage* / Q000097:blood / Q000378:metabolism / Q000493:pharmacokinetics*; D019540:Area Under Curve; D004334:Drug Administration Schedule; D005260:Female; D006207:Half-Life; D008168:Lung / Q000378:metabolism*; D011817:Rabbits; D014018:Tissue Distribution; D015645:Tylosin / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000097:blood / Q000378:metabolism / Q000493:pharmacokinetics
D000900:Anti-Bacterial Agents; C052319:tilmicosin; D015645:Tylosin