Toxicokinetics of cinnamaldehyde in F344 rats.
The toxicokinetic profile of cinnamaldehyde (CNMA) was investigated in Fischer 344 rats. CNMA was found to be unstable in blood. After iv administration, a large fraction of CNMA was immediately oxidized to cinnamic acid. The biological half-life of CNMA after iv administration was found to be 1.7 hr. After administration by gavage of CNMA at 250 or 500 mg/kg body weight using corn oil as vehicle, the maximum blood concentrations of CNMA were in the order of 1 microgram/ml. These low blood concentrations were maintained over a 24-hr period after a dose of 500 mg/kg, which is relatively long considering the short (1.7 hr) biological half-life of CNMA. The estimated oral bioavailability of CNMA was less than 20% for both the 250 and 500 mg/kg doses. No CNMA was present in blood at any time in rats dosed with 50 mg CNMA/kg body weight. Only a small amount of the administered CNMA was excreted in rat urine as free cinnamic acid or beta-glucuronide-conjugated cinnamic acid. The majority of CNMA administered orally was excreted in urine as hippuric acid within 24 hr. The maximum excretion rate occurred at 8 hr after gavage. Hippuric acid recovered in 50-hr urine samples was found to be directly proportional to the oral dose of CNMA.
Yuan
J H
JH
National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709.
Dieter
M P
MP
Bucher
J R
JR
Jameson
C W
CW
D000171:Acrolein / Q000031:analogs & derivatives* / Q000097:blood / Q000493:pharmacokinetics / Q000633:toxicity; D000284:Administration, Oral; D000818:Animals; D001682:Biological Availability; D002934:Cinnamates / Q000652:urine; D005260:Female; D006207:Half-Life; D006626:Hippurates / Q000652:urine; D007275:Injections, Intravenous; D008297:Male; D051381:Rats; D011916:Rats, Inbred F344
D002934:Cinnamates; D006626:Hippurates; C029010:cinnamic acid; D000171:Acrolein; C012843:cinnamaldehyde; C030514:hippuric acid