title: Pharmacokinetics of sulphadimethoxine in the lobster, Homarus americanus, following intrapericardial administration.
abstract: 1. The pharmacokinetics and tissue distribution of intrapericardially administered sulphadimethoxine were studied in the lobster Homarus americanus. 2. Pharmacokinetic analysis of haemolymph concentration-time data indicated that a two compartment model best described sulphadimethoxine disposition, and that there were no apparent sex differences in the lobster. Analysis of total body clearance (Clb), apparent steady-state volume of distribution (Vss), area under the curve, and plasma protein binding in lobsters receiving 21, 42 and 55 mg/kg sodium sulphadimethoxine indicated that the pharmacokinetics were independent of dose. 3. Mean parameter estimates for Clb, Vss, and terminal half life were 13.8 ml/h/kg, 1369 ml/kg, and 76.7 h, respectively. Binding of sulphadimethoxine to haemolymph proteins was linear, with a mean of 53.5% bound. 4. Analysis of the tissue distribution of radiolabelled sulphadimethoxine at 4, 48 and 336 hours after a 42 mg/kg dose indicated that sulphadimethoxine was excreted slowly by the lobster, with the muscle, shell and haemolymph holding the largest fraction of the dose at early times. After 2 weeks, 9.5% of the radiolabel remained in the animal, with the hepatopancreas and digestive tract holding the greatest concentration of the dose.
authors: C. V. Whitney Laboratory, University of Florida, St. Augustine 32086.
authors: M G
authors: MG
authors: Barron
authors: C
authors: C
authors: Gedutis
authors: M O
authors: MO
authors: James
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000493:pharmacokinetics*; D005260:Female; D006458:Hemolymph / Q000378:metabolism; D008297:Male; D009132:Muscles / Q000378:metabolism; D008121:Nephropidae / Q000378:metabolism*; D012737:Sex Factors; D013412:Sulfadimethoxine / Q000008:administration & dosage / Q000493:pharmacokinetics*; D014018:Tissue Distribution
chemical_list: D000900:Anti-Bacterial Agents; D013412:Sulfadimethoxine