Related Experiment Video
Updated: Jun 9, 2026

Microsurgical Skills of Establishing Permanent Jugular Vein Cannulation in Rats for Serial Blood Sampling of Orally Administered Drug
Published on: December 14, 2021
Pharmacokinetics and first-pass metabolism of astaxanthin in rats
Hye Duck Choi1, Hee Eun Kang, Si Hyung Yang
1College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, San 56-1, Sillim-Dong, Gwanak-Gu, Seoul 151-742, South Korea.
Abstract:
Astaxanthin is a carotenoid with antioxidant, anti-cancer and anti-inflammatory properties. The pharmacokinetics of astaxanthin after its intravenous (5, 10, and 20 mg/kg) and oral (100 and 200 mg/kg) administration and its first-pass extraction ratios after its intravenous, intraportal or intragastric (20 mg/kg) administration were evaluated in rats. The pharmacokinetic parameters of astaxanthin were dose dependent after its intravenous administration, due to the saturable hepatic metabolism of astaxanthin, but dose independent after oral administration. The gastrointestinal absorption of astaxanthin followed the flip-flop model. The hepatic and gastrointestinal first-pass extraction ratios of astaxanthin were approximately 0·490 and 0·901, respectively. Astaxanthin was metabolised primarily by hepatic cytochrome P-450 1A1/2 in rats. Astaxanthin was unstable up to 4 h incubation in four rat gastric juices and up to 24 h incubation in various buffer solutions having a pH of 1-13. The tissue/plasma ratios of astaxanthin at 8 and 24 h after its oral administration (100 mg/kg) were greater than unity for all tissues studied, except in the heart, at 8 h, indicating that the rat tissues studied had high affinity for astaxanthin.
Related Concept Videos
First Pass Effect
Depending on the route of administration, drugs can be metabolized in the liver, intestine, lungs, and vasculature. Orally administered drugs are first absorbed through the...
Pharmacokinetics in Geriatric Patients: Effect of Age on Drug Metabolism
Pharmacokinetics in Pediatric Patients: Drug Metabolism
Factors Influencing Bioavailability: First-Pass Elimination
Factors Influencing Drug Absorption: Presystemic Elimination
Measurement of Bioavailability: Pharmacokinetic Methods

