Pharmacokinetics of sulfluramid and its metabolite desethylsulfluramid after intravenous and intraruminal administration of sulfluramid to sheep

✍ Scribed by Vitayavirasuk, Banjong; Bowen, John M

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 118 KB
• Volume: 55
• Category: Article
• ISSN: 1526-498X
• DOI: 10.1002/(sici)1096-9063(199907)55:7<719::aid-ps9>3.0.co;2-b

✦ Synopsis

Pharmacokinetic properties and tissue residues of the insecticide sul¯uramid (I) and its major metabolite desethylsul¯uramid (II) were determined in healthy sheep after bolus intravenous (IV) administration (5 and 15 mg kg À1 ; n = 10) and bolus intraruminal (IR) administration (100 and 400 mg kg À1 ; n = 12) of I. Depression, lethargy, and dyspnea were noted for 4 h after the higher IV dose, but not after the other IV or IR doses. The time courses of the mean blood concentrations of I and II were best described by a two-compartment open model with rapid distribution and slow elimination phases. The blood-to-plasma concentration ratios for I and II were 1.43 (AE 0.50) and 26.7 (AE 9.41), respectively, suggesting binding of II to red blood cells. The T 1/2b values for I and II for the higher IV dose of I were 15.3 (AE 4.68) h and 63.4 (AE 4.75) h and for the higher IR dose of I, 31.5 (AE 5.41) h and 74.9 (AE 7.49) h, respectively. Bioavailability was 28.6 (AE 2.96)% for the lower IR dose and 19.5 (AE 0.99)% for the higher IR dose. C max values for II were higher in female than male sheep after IR administration of I. Only II was found in tissue samples, with the highest concentration being in liver (9.4 (AE 5.2) mg g À1 ).