The effect of intravenous pretreatment with small liposomes on the pharmacokinetics and metabolism of antipyrine in rabbits.
The effect of intravenous pre-treatment with empty small liposomes on the pharmacokinetics and metabolism of antipyrine in rabbits has been investigated. The measured half-life of antipyrine was 104 min and the volume of distribution was 830 mL kg-1. The excretion of metabolites in a 24 h urine sample was measured, the main metabolite 4-hydroxyantipyrine was excreted to a level of 10% with the free drug accounting for 4%. The norantipyrine and 3-hydroxymethylantipyrine metabolites were excreted to a level of 8 and 7%, respectively. The intravenous administration of liposomes at a dose equivalent to 8 mg of egg yolk phosphatidylcholine daily for one week, had no significant effect on any of the measured pharmacokinetic parameters. The half-life after liposome treatment was 110 min and the volume of distribution was 790 mL kg-1, the metabolic pattern in the urine was also unaltered. The results suggest that the repeated administration of low doses of liposomes do not affect the pharmacokinetics and metabolism of antipyrine.
Pharmacy Department, School of Pharmacy and Pharmacology, Strathclyde University, Glasgow, UK.
N
N
Badiola
A N
AN
Al-Angary
G W
GW
Halbert
D000818:Animals; D000983:Antipyrine / Q000378:metabolism / Q000493:pharmacokinetics*; D002851:Chromatography, High Pressure Liquid; D006207:Half-Life; D007275:Injections, Intravenous; D008081:Liposomes / Q000008:administration & dosage* / Q000494:pharmacology; D008297:Male; D011817:Rabbits; D013057:Spectrum Analysis
D008081:Liposomes; D000983:Antipyrine